Part 1. Measurement
1. Which of the following pairs of physical quantities has the same dimensions?
(a) Work and power
(b) Momentum and energy
(c) Force and power (d) Work and energy
Ans: (d)
2. Which of the following pairs is wrong?
(a) Pressure — Barometer
(b) Relative density — Pyrometer
(c) Temperature — Thermometer
(d) Earthquake — Seismograph
Ans: (b)
3. Which one of the following is a vector quantity?
(a) Momentum (b) Pressure
(c) Energy (d) Work
Ans: (a)
4. Match the columns
List I (Quantity) List II (Unit)
A. Luminous intensity 1. Kelvin
B. Amount of substance 2. Candela
C. Time 3. Second
D. Temperature 4. Mole
Codes A B C D A B C D
(a) 2 4 3 1 (b) 4 2 3 1
(c) 2 4 1 3 (d) 3 1 4 2
Ans: (a)
5. The SI unit of acceleration is
(a)ms–1
(b)ms–2
(c) cms–2
(d) kms–2
Ans: (b)
6. One astronomical unit is the average distance between
(a) Earth and the Moon
(b) Earth and the Sun
(c) Jupiter and the Sun
(d) Pluto and the Sun
Ans: (b)
7. Match List I (Quantity) with List II (Unit) and select the correct answer using the codes given below
List I List II
A. High speed 1. Mach number
B. Wavelength 2. Angstrom
C. Pressure 3. Pascal
D. Energy 4. Joule
Codes A B C D
(a) 2 1 4 3
(b) 2 1 3 4
(c) 1 2 4 3
(d) 1 2 3 4
Ans: (d)
8. The SI unit of mechanical power is
(a) Joule (b) Watt
(c) Newton-second (d) Joule-second
Ans: (b)
9. Consider the following statements
1. The magnitude of vector is always a scalar.
2. The total path length is always equal to the magnitude of the displacement vector of a particle.
3. The average speed of a particle is either greater or equal to the magnitude of the average velocity of the particle over the same interval of time.
4. Three vectors not lying in a plane can never add up to give a null vector.
Which of the statements given above is/are correct?
(a) 1, 2 and 3
(b) 1, 3 and 4
(c) 1, 2 and 4
(d) 1, 2, 3 and 4
Ans: (b)
10. Match List I with List II and select the correct answer using the codes given below
List I List II
A. Joule 1. Henry-ampere/sec
B. Watt 2. Farad-volt
C. Volt 3. Coulomb-volt
D. Coulomb 4. Oersted-cm 5. Amp-gauss
6. Amp2-ohm
Codes A B C D A B C D
(a) 1 6 5 4 (b) 3 6 1 2
(c) 3 6 1 5 (d) 2 6 1 3
Ans: (c)
11. In the relation α/t +, αand are measured in metre (m) and t is measured in second (s). The SI unit ofmust be
(a) m (b) ms (c) s (d) ms-1
Ans: (d)
12. Match List I with List II and select the correct answer using the codes given below
List I List II
A. Acceleration 1. Joule
B. Force 2. Newton second
C. Work done 3. Newton
D. Impulse 4. Metre per second2
Codes A B C D
(a) 1 2 3 4
(b) 2 3 4 1
(c) 4 3 1 2
(d) 3 4 1 2
Ans: (c)
13. Which of the following physical quantities is dimensionless?
(a) Strain (b) Angle
(c) Specific gravity (d) All of these
Ans: (d)
14. Match List I with List II and select the correct answer from the codes given below
List I List II
A. Joule 1. Current
B. Ampere 2. Power
C. Watt 3. Work
D. Volt 4. Potential difference
E. Calorie 5. Heat
Codes A B C D E
(a) 3 1 2 4 5
(b) 1 2 3 4 5
(c) 4 3 2 1 5
(d) 1 3 2 4 5
Ans: (a)
15. Which of the following physical quantities have the same dimensions?
(a) Momentum and impulse
(b) Force constant and moment of inertia
(c) Energy and angular momentum
(d) Power and Young’s modulus
Ans: (a)
16. Maxwell is the unit of
(a) permeability (b) magnetic flux
(c) magnetic susceptibility
(d) intensity of magnetisation
Ans: (b)
17. If the density of water is 1g cm–3 in CGS system, its value inMKS systemis
(a) 1 kg m–3 (b) 103 kg m–3
(c) 10–3 kg m–3 (d) 10–6 kg m–3
Ans: (b)
18. Which of the following is not matched?
(a) Decibel – Unit of sound
(b) Horse power – Unit of power
(c) Nautical mile – Unit of distance
(d) Celsius – Unit of heat
Ans: (d)
19. Potential is measured in
(a) watt (b) joule
(c) joule/coulomb (d) Newton-second
Ans: (c)
20. One light year is approximately equal to
(a) 1011km (b) 1015m
(c) 106m (d) 1016 km
Ans: (c)
21. Consider the physical quantities
1. Electric current 2.Work
3. Temperature
4. Density
Which of the above are scalar quantities?
(a) 1, 2 and 3 (b) 1, 4 and 3
(c) 3, 4 and 2 (d) 1, 2, 3 and 4
Ans: (d)
22. Which one of the following pairs of physical quantities may be represented in the same unit?
(a) Temperature and mole
(b) Heat and work
(c) Heat and temperature
(d) Specific heat and heat
Ans: (b)
23. Consider the physical quantities
1. Displacement
2. Torque
3. Current density
4. Linear momentum
Which of the given are vector quantities?
(a) 3, 4 and 2 (b) 1, 4 and 3
(c) 1, 2 and 3 (d) 1, 2, 3 and 4
Ans: (d)
24. Masses of stars and galaxies are usually expressed in terms of
(a) neutron mass
(b) Earth’s mass
(c) solar mass
(d) lunar mass
Ans: (c)
25. Consider the following statements
1. All plane angles are measured in radian.
2. All the solid angles are measured in steradian.
3. Solid angle is measured in steradian.
Which of the statements given above is/are correct?
(a) Only 1 (b) Only 3
(c) 2 and 3 (d) 1, 2 and 3
Ans: (d)
26. The displacement of a particle at time is given by x = aj +bj + c/2 t2k where a, b and c are positive constants. Then the particle is
(a) accelerated along k-direction
(b) decelerated along k-direction
(c) decelerated along j-direction
(d) accelerated along j-direction
Ans: (a)
27. Unit of resistance is
(a) volt -ampere (b) volt2 -ampere
(c) volt/ampere (d) ampere/volt
Ans: (c)
28. In SI unit of force ‘Newton’ (N) is given by (where ‘m’ stands for ‘metre’ and ‘s’ stands for second)
(a) 1 N = 1 kg/ms2
(b) 1 N = 1 kgm/s2
(c) 1 N = 1 kgs2/m
(d) 1 N = 1 kgms2
Ans: (b)
Part 2. Motion
29. A ball P is dropped vertically and another ball Q is thrown horizontally with the same velocities from the same height and at the same time. If air resistance is neglected, then
(a) ball P reaches the ground first.
(b) ball Q reaches the ground first.
(c) both reach the ground at the same time.
(d) the respective masses of the two balls will decide the time.
Ans: (c)
30. Which of the following statements is false?
(a) A body can have zero velocity and still be accelerated.
(b) A body can have a constant velocity and still have a varying speed.
(c) A body can have a constant speed and still have varying velocity.
(d) The direction of the velocity of a body can change when its acceleration is constant.
Ans: (b)
31. Assertion (A) When a gun is fired i.e., it pushes back, with much less velocity than the velocity of the bullet.
Reason (R) Velocity of the recoiling gun is less because the gun is much heavier than bullet.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true, but R is not the correct explanation of A
(c) A is true, but R is false
(d) A is false, but R is true
Ans: (a)
32. For amoving body at any instant of time
(a) if the body is not moving, the acceleration is necessarily zero.
(b) if the body is slowing, the retardation is negative.
(c) if the body is slowing, the distance is negative.
(d) if displacement, velocity and acceleration at that instant are known, we can find the displacement at any given time in future.
Ans: (d)
33. A car is moving with a uniform speed. However, its momentum is changing. Then the car
(a) may be on an elliptical path.
(b) is moving on a straight path without acceleration.
(c) is moving on a straight path with acceleration.
(d) is moving without any acceleration.
Ans: (d)
34. A ball is thrown upwards and it returns to ground describing a parabolic path. Which of the following remains constant?
(a) Kinetic energy of the ball
(b) Speed of the ball
(c) Horizontal component of velocity
(d) Vertical component of velocity
Ans: (c)
35. If the distance S covered by a moving car in rectilinear motion with a speed v in time t is given by S = vt, then the car undergoes
(a) a uniform acceleration
(b) a non-uniform acceleration
(c) a uniform velocity
(d) a non-uniform velocity
Ans: (c)
36. Which one of the following statements is not correct?
(a) If the velocity and acceleration have opposite sign, the object is slowing down.
(b) If the velocity is zero at an instant, the acceleration should also be zero at that instant.
(c) If the velocity is zero for a time interval, the acceleration is zero at any instant within the time interval.
(d) So, the position and velocity have opposite sign the object is moving towards the origin.
Ans: (b)
37. The force required to keep a body in uniform circular motion is
(a) centripetal force (b) centrifugal force
(c) resistance (d) None of these
Ans: (b)
38. The displacement of a particle is given by x /cos t 2 . The motion is
(a) simple harmonic
(b) periodic but not simple harmonic
(c) non-periodic
(d) None of the above
Ans: (a)
39. The motion of a car along a straight path is shown by the following figure The car starts from O and reaches at A, B and C at different instants of time. During its motion from O to C and back to B, the distance covered and the magnitude of the displacement are, respectively
(a) 25 km and 60 km
(b) 95 km and 35 km
(c) 60 km and 25 km
(d) 85 km and 35 km
Ans: (d)
40. A person is sitting in a moving train and facing the engine. He tosses up a coin and coin falls behind him. It can be concluded that the train is
(a) moving forward and gaining speed
(b) moving forward and losing speed
(c) moving forward with uniform speed
(d) moving backward with uniformspeed
Ans: (b)
41. Consider the following statements
1. In railway track or road, the inner track/edge is comparatively less in height than the outer.
2. Washing machine is working on the principle of centrifugation.
3. A car takes a turn on level road. Itmay be thrown outwards because of the lack of centripetal force.
Which of the statements given above is/are correct?
(a) 1, 2 and 3 (b) 1 and 3
(c) 2 and 3 (d) Only 3
Ans: (a)
42. An athlete diving off high spring board can perform a variety of exercise in the air before entering the water body. Which one of the following parameter will remain constant during the fall?
(a) The athlete’s linear momentum
(b) The athlete’s angular momentum
(c) The athlete’s kinetic energy
(d) The athlete’s moment of inertia
Ans: (a)
43. Which of the following statements are correct when a gymnast sitting on a rotating stool with his arms outstretched, suddenly lowers his hands?
1. The angular velocity decreases.
2. The angular velocity increases.
3. The moment of inertia decreases.
4. The moment of inertia increases. Select the answers using the codes given below.
(a) 1 and 3 (b) 1 and 4
(c) 2 and 3 (d) 2 and 4
Ans: (b)
44. A racing car accelerates on a straight line from rest to a speed of 50 m/s in 25 m. Assuming uniform acceleration of the throughout, the distance covered in this time will be
(a) 625 m (b) 1250 m
(c) 2500 m (d) 50 m
Ans: (a)
45. A cricket player catches a fast coming ball by pulling his hands back because
(a) the ball can come to a position of rest
(b) the ball can be accelerated
(c) the ball can exert a greater force
(d) the ball can exert a lesser force
Ans: (c)
46. A person is sitting in a car which is at rest. The reaction from the road at each of the four wheels of the car isR. When the car runs on a straight level road, how will the reaction at either of the front wheels vary?
(a) It will be greater than R
(b) It will be less than R
(c) It will be equal to R
(d) It shall depend on the materials of the road
Ans: (a)
47. Consider the following statements
1. Centrifugal force is exerted by a cream separator machine of the milk.
2. A horse suddenly moves then it is a fear to fall down the horse rider because of inertia of rest.
3. The bodies executing free falling motion have equal momentum.
(a) 1, 2 and 3 (b) 1 and 2
(c) 3 and 2 (d) Only 1
Ans: (b)
48. An object is undergoing a non-accelerated motion. Its rate of change in momentum is
(a) a non-zero constant
(b) zero
(c) not a constant
(d) None of these
Ans: (c)
49. The cat survive fall from height much more than human or any other animal. It is because the cat
(a) has elastic bones
(b) has thick and elastic skin
(c) can immediately adjust itself to land on all four paws and absorbs the impact of fall by bending
(d) None of the above
Ans: (b)
50. A passenger in a moving train tosses a five rupees coin. If the coin falls behind him, then the train must be moving with a uniform
(a) acceleration
(b) deceleration
(c) speed
(d) velocity A 30 35 40 45 50 55 60 B C km O 0
Ans: (c)
51. A piece of paper and a cricket ball are dropped from the same height. Under which of the following conditions do both reach the surface simultaneously?
(a) They must have the same volume
(b) They must have the same density
(c) They must have the same mass
(d) They must be dropped in vacuum
Ans: (a)
52. Match the following lists
List I List II
A. Motion of billiards ball 1. One-dimensional motion
B. Motion of flying insect 2. Two-dimensional motion
C. Motion of freely falling body 3. Three-dimensional motion
Codes A B C A B C
(a) 1 2 3 (b) 1 2 3
(c) 2 3 1 (d) 3 2 1
Ans: (b)
53. For a particle revolving in a circular path with constant speed, the acceleration of the particle is
(a) along the tangent
(b) along the radius (c) zero
(d) along the circumference of the circle
Ans: (c)
54. Two stones of unequal masses are thrown vertically up with the same velocity. Which of the following will happen?
(a) The heavier mass will reach greater height
(b) The lighter mass will reach greater height
(c) Both will reach the same height
(d) Any of themmay reach greater height
Ans: (c)
55. Water flows out of the hole of a bucket and follows a parabolic path. If the bucket falls freely under gravity, the water flow (ignoring air resistance)
(a) follows a straight line path relative to the falling bucket
(b) follows a parabolic path relative to the falling bucket
(c) stops
(d) decreases but continues to flow
Ans: (c)
56. Which one of the following graphs represents uniform motion?
Ans: (d)
57. A body has a free fall from a height of 20 m. After falling through a distance of 5 m, then body would
(a) lose one-fourth of its total energy
(b) lose one-fourth of its potential energy
(c) gain one-fourth of its potential energy
(d) gain three-fourth of its total energy
Ans: (a)
58. Assertion (A) The average velocity of the object over an interval of time is either smaller than or equal to the average speed of the object over the same interval.
Reason (R) Velocity is a vector quantity and speed is a scalar quantity.
(a) Both A and R are correct and R is true explanation of A
(b) Both A and R are correct but R is not true explanation of A
(c) A is correct and R is wrong
(d) A is wrong and R is correct
Ans: (b)
59. A motor vehicle is moving on a circle with a uniform speed. The net acceleration of the vehicle is
(a) zero
(b) towards the centre of the circle
(c) away from the centre along the radius of the circle
(d) perpendicular to the radius and along the velocity
Ans: (b)
60. An object with a constant speed
(a) is always accelerated
(b) is not accelerated
(c) might be accelerated
(d) also has a constant velocity
Ans: (c)
61. A bus travels at a speed of 50 km/h to go from its origin of its destination at a distance of 300 km and travels at a speed of 60 km/h to return to the origin. What is the average speed of the bus?
(a) 54.55 km/h (b) 55 km/h
(c) 55.55 km/h (d) 54 km/h
Ans: (a)
62. A particle is moving in a circular path of radius r at a constant speed v. Which one of the following graphs correctly represents its acceleration a?
Ans: (d)
63. A body moves with a constant speed along a curved path, its acceleration
(a) is zero
(b) is parallel to its velocity
(c) can make any arbitrary angle with its velocity
(d) is perpendicular to its velocity
Ans: (c)
64. A man in a train moving with constant velocity drops a ball on the platform. The path of the ball as seen by an observer standing on the platform is
(a) a straight line (b) a circle
(c) a parabola (d) None of these
Ans: (c)
65. A spherical body moves with uniform angular velocity () around a circular path of radius r, which one of the following statement is correct ?
(a) The body has no acceleration
(b) The body has a radial acceleration 2r directed towards centre of path
(c) The body has a radial acceleration 2/52r directed away from the centre of the path
(d) The body has an acceleration 2 tangential to its path.
Ans: (b)
66. The Earth without rotational movement would result into
1. no Sun-rise and Sun-set.
2. no occurrence of day and night cycle.
3. only one season. Select the correct answer using the codes given below
(a) Only 1 (b) 1 and 2
(c) 2 and 3 (d) 1, 2 and 3
Ans: (b)
67. If an object undergoes a uniform circular motion, then its
(a) acceleration remains uniform
(b) velocity changes
(c) speed changes
(d) velocity remains uniform
Ans: (b)
68. A car is running on a road at a uniform speed of 60 km/h. The net resultant force on the car is
(a) driving force in the direction of car’s motion
(b) resistance force opposite to the direction of car’s motion
(c) an inclined force
(d) equal to zero
Ans: (d)
69. A body starting from the rest moves along a straight line with constant acceleration. Which one of the following graphs represents the variation of speed (v) and distance (s) ?
Ans: (c)
70. Fat can be separated from milk in a cream separator because of
(a) cohesive force
(b) gravitational force
(c) centripetal force (d) centrifugal force
Ans: (d)
71. If d denotes the .distance covered by a car in time t and S denotes the displacement by the car during the same time, then
(a) d /S
(b) d-S
(c) d .S
(d) d+S
Ans: (c)
72. For a body moving with constant speed in a horizontal circle, which of the following remains constant?
(a) Velocity (b) Acceleration
(c) Centripetal force (d) KE
Ans: (d)
73. A brick is thrown vertically from an aircraft flying two kilometres above the Earth. The brick will fall with a
(a) constant speed
(b) constant velocity
(c) constant acceleration
(d) constant speed for some time then with constant acceleration as it nears the Earth
Ans: (c)
Part 3. Work, Power & Energy
74. A brass ball is tied to a thin wire and swung so as to move uniformly in a horizontal circle. Which of the following statements in this regard is/are true?
1. The ballmoves with constant velocity.
2. The ball moves with constant speed.
3. The ball moves with constant acceleration.
4. The magnitude of the acceleration of the ball is constant. Select the correct answer using the code given below
(a) Only 1
(b) 1 and 3
(c) 1, 2 and 4
(d) 2 and 4
Ans: (d)
75. Consider the following statements
1. When a coolie carrying a load on his head moves on a horizontal platform, the work done by the coolie against gravity is zero.
2. When a satellite revolves in a circular orbit around the Earth, the work done by the gravitational force on the satellite is zero.
3. When a body falls freely under gravity, the work done by gravity is negative.
4. Work is a scalar quantity.
Which of the statements given above is/are correct?
(a) 1 and 2 (b) 2 and 3
(c) Only 4 (d) 1, 2 and 4
Ans: (d)
76. Which among the following graphs represent a body is moving with infinite velocity?
Ans: (a)
77. If a light body and a heavy body have equal momentum, then
(a) the lighter body has greater kinetic energy than the heavier body
(b) the lighter body has lesser kinetic energy than the heavier body
(c) the kinetic energy of the lighter body is equal to the kinetic energy of the heavier body
(d) the kinetic energy of both the bodies are independent of momentum
Ans: (a)
78. Two bodies A and B are moving with equal velocities. The mass of B is double that of A. In this context, which one of the following statements is correct?
(a) Momentum of B will be double that of A.
(b) Momentum of A will be double that of B.
(c) Momentum of B will be four times that of A.
(d) Momentum of both A and B will be equal.
Ans: (a)
79. A cyclotron accelerates particles of mass m and charge q. The energy of particles emerging is proportional to
(a) q/m 2
(b) q2/m
(c) q2/m2
(d) q
Ans: (a)
80. A ball is dropped from height 5 m. Ball is embedded in sand 1 m and stops, then
(a) only momentum remains conserved
(b) only kinetic energy remains conserved
(c) both momentum and KE are conserved
(d) either KE nor momentum is conserved
Ans: (d)
81. In an elastic collision,
1. the kinetic energy remains constant.
2. the linear momentum remains constant.
3. the final kinetic energy is equal to the initial kinetic energy.
4. the final linear momentum is equal to the initial linear momentum.
Which of the statements given above are correct?
(a) 1 and 3 (b) 1, 2, 3 and 4
(c) 2 and 3 (d) Only 4
Ans: (d)
82. An object is raised to a height of 3 m from the ground. It is then allowed to fall on to a table 1 m high from ground level. In this context, which one among the following statements is correct?
(a) Its potential energy decreases by two-thirds its original value of total energy
(b) Its potential energy decreases by one-third its original value of total energy
(c) Its kinetic energy increases by two-thirds while potential energy increases by one-third
(d) Its kinetic energy increases by one-third, while potential energy decreases by one-third
Ans: (a)
83. Which of the following statements are correct when a body dropped from a high building explodes into two pieces of equal mass in the mid air?
1. Each part will show parabolic path.
2. Only one part will show the parabolic path.
3. Both parts will move along a vertical line.
4. One part will reach the ground earlier than other. Select the correct option using the codes given below.
(a) 1, 2, 3 and 4 (b) 1, 2 and 3
(c) 1, 3 and 4 (d) 3 and 4
Ans: (b)
84. A metal ball and a rubber ball of the same mass are dropped from the same height. After hitting the floor, the rubber ball rises higher than the metal ball, why?
(a) Momentum is not conserved when the metallic ball hits the floor
(b) The rubber ball hits the floor with greater velocity
(c) Momentum is not conserved when rubber ball hits the floor
(d) None of the above
Ans: (d)
85. Consider the following statements
1. In elastic collision, the momentum is conserved but not in inelastic collision.
2. Both kinetic energy and momentum are conserved in elastic as well as inelastic collision.
3. Total kinetic energy is not conserved but momentum is conserved in inelastic collision.
4. Total kinetic energy is conserved in elastic collisions butmomentumis not conserved in elastic collisions.
Which of the statement(s) given above is/are true?
(a) 1, 2 and 3 (b) Only 3
(c) 2 and 4 (d) All of these
Ans: (b)
86. The impulse on a particle due to a force acting on it during a given time interval is equal to the change in its
(a) force (b) momentum
(c) work done (d) energy
Ans: (b)
87. Match the columns
List I List II
A. In an electric heater 1. Chemical energy is converted into heat energy
B. In an electric bulb 2. Heat energy is converted into mechanical energy
C. In burning of coal 3. Electrical energy is converted into light energy
D. In steam engine 4. Electrical energy is converted into heat energy
Codes A B C D A B C D
(a) 4 3 1 2 (b) 3 4 1 2
(c) 1 2 3 4 (d) 4 3 2 1
Ans: (a)
88. In which case does the potential energy decrease?
1. On compressing a spring.
2. On stretching a spring.
3. On moving a body against gravitational force.
4. On the rising of an air bubble in water. Select the correct answer using the codes given below.
(a) 1 and 2 (b) Only 4
(c) 3 and 4 (d) All of these
Ans: (a)
89. Consider the following statements
1. Work done by a centripetal force is always zero.
2. When a body falls, potential energy is converted into kinetic energy.
3. The power of a body is defined as its capacity of doing work.
Which of the statement(s) given above is/are correct?
(a) 1 and 2 (b) 2 and 3
(c) 1, 2 and 3 (d) None of these
Ans: (a)
90. Which of the following are the characteristic of an inelastic collision?
1. Momentum is conserved.
2. Total energy is conserved.
3. Kinetic energy is conserved.
4. All the forces must be of conservative nature. Select the correct answer using the codes given below
(a) 3 and 4 (b) 1 and 2
(c) 1 , 2 and 4 (d) 2 and 4
Ans: (c)
91. Which one of the following is a convention energy source?
(a) Tidal energy
(b) Geothermal energy
(c) Solar energy (d) Biomass energy
Ans: (d)
92. Consider the following statements
1. The work done by a body against friction always causes a loss in the kinetic energy.
2. In an inelastic collision of two bodies, the total energy of the system changes to some other form but the linear momentum and kinetic energy remain unchanged.
Which of the statement (s) given above is/are correct?
(a) 1 and 2 (b) Only 1
(c) Only 2 (d) None of these
Ans: (b)
93. A force F is applied on a body (which moves on a straight line) for a duration of 3 s. The momentum of the body changes from 10 g cm/s to 40 g cm/s. The magnitude of the force F is
(a) 10 dynes (b) 10 newtons
(c) 120 dynes (d) 12 dynes
Ans: (a)
94. A bullet hits and gets embedded in a solid block resting on a horizontal frictionless table. What is conserved?
(a) Momentum
(b) Momentum and KE
(c) KE
(d) Neither momentum nor KE
Ans: (d)
95. Consider the following statements
1. A force is said to be conservative if the work done by the force on a particle in a round trip is zero.
2. A force is said to be non-conservative if work done by the force on a particle in a round trip is not zero.
3. The gravitational force and the electrostatical force are the examples of non-conservative forces.
4. Viscous force and frictional force are the examples of conservative forces.
Which of the statements given above are in correct?
(a) 1, 2 and 3
(b) 1 and 2
(c) 3 and 4
(d) 1, 2, 3 and 4
Ans: (d)
96. Match the following lists
List I List II (Equipments/ Instruments) (Transformation of Energy)
A. Dynamo 1. Sound energy to Electrical energy
B. Microphone 2. Mechanical energy into electrical energy
C. Loudspeaker 3. Mechanical energy into sound energy
D. Musical Instrument 4. Electrical energy into sound energy
Codes A B C D A B C D
(a) 1 2 3 4 (b) 2 1 4 3
(c) 4 3 2 1 (d) 3 4 2 1
Ans: (b)
97. Consider the following statements about KE
1. If the mass of the body is made double then its kinetic energy will become double.
2. If either velocity or linear momentum of the body is double, its KE will become four times as that of original.
Which of the statement(s) given above is/are correct?
(a) Only 1
(b) Only 2
(c) Both 1 and 2
(d) Neither 1 nor 2
Ans: (c)
98. Two bodies A and B having masses m and 4m respectively are moving with equal linear momentum. The ratio of kinetic energies between A and B is
(a) 1 : 4 (b) 4 : 1
(c) 1 : 1 (d) 1 : 2
Ans: (b)
99. The rate of change of momentum of a body is equal to the resultant
(a) energy (b) power
(c) force (d) impulse
Ans: (c)
Part 4. Friction
100. Consider the following statements
1. Electric cell converts chemical energy into electrical energy.
2. Candle converts chemical energy into light energy and thermal energy.
Which of the statements given above is/are correct?
(a) Only 1 (b) Only 2
(c) Both 1 and 2 (d) Neither 1 nor 2
Ans: (c)
101. Which of the following is correct, when a person walks on a rough surface?
(a) The frictional force exerted by the surface keeps him moving
(b) The force which the man exerts on the floor keeps him moving
(c) The reaction of the force which the man exerts on floor keeps him moving
(d) None of the above
Ans: (c)
102. If a bomb dropped from an airplane explodes in mid-air
(a) its KE increases
(b) its total energy increases
(c) its total energy decreases
(d) None of the above
Ans: (c)
103. To avoid slipping while walking on ice, one should take smaller steps because of the
(a) friction of ice is large
(b) larger normal reaction
(c) friction of ice is small
(d) smaller normal reaction
Ans: (c)
104. When a bicycle is in motion by pedalling, the force of friction exerted by the ground on the two wheels is such that it acts
(a) in the backward direction on the front wheel and in the forward direction on the rear wheel
(b) in the forward direction on the front wheel and in the backward direction on the rear wheel
(c) in the backward direction on both front and the rear wheels
(d) in the forward direction on both front and the rear wheels
Ans: (a)
105. Consider the following statements
1. The maximum static frictional force is equal to the area of surface in contact.
2. The maximum static frictional force is independent of the area of surface in contact.
3. The limiting friction is always greater than the dynamic friction.
4. The coefficient of friction between two surfaces increases as the surface in contact are made rough.
Which of the statement(s) is/are not true?
(a) 1 and 2 (b) Only 1
(c) 2, 3 and 4 (d) 3 and 4
Ans: (a)
106. Consider the following statements
1. The force of friction acts in a direction opposite to the applied force.
2. Rolling friction is greater than sliding friction.
3. Work done by a frictional force may be negative, positive or zero.
Which of the statement (s) is/ are true?
(a) 1, 2 and 3 (b) Only 2
(c) 1 and 3 (d) 1 and 2
Ans: (c)
107. When a body is lying on a rough inclined plane and does not move, the force of friction
(a) is equal to R (b) is less than R
(c) is greater than R
(d) is equal to R
Ans: (b)
108. Consider the following statements
1. Friction is a non-conservative force which always opposes themotion of a body over the other.
2. The usual methods of reducing friction are polishing of surfaces, lubrication with oil or grease, use of ball bearings etc.
3. Friction due to air is considerably reduced by streamlining the shape of the body.
4. Friction depends upon the nature of the material of surfaces in contact.
Which of the statement(s) is/are correct?
(a) 1 and 2 (b) 2 and 3
(c) 1, 2, 3 and 4 (d) Only 4
Ans: (c)
109. Consider the following pairs of substances/situation
1. Piece of teflon on another piece of teflon.
2. A block of ice on another block of ice.
3. Rubber tyre on a wet road.
4. Rubber tyre on a dry road. The correct sequence of the decreasing order of their magnitude of the coefficient of friction is
(a) 4, 3, 2, 1 (b) 4, 3, 1, 2
(c) 3, 4, 2, 1 (d) 3, 4, 1, 2
Ans: (a)
110. Angle of friction and angle of repose are
(a) equal to each other
(b) not equal to each other
(c) proportional to each other
(d) None of the above
Ans: (a)
111. Consider a vehicle going on a horizontal road towards east. Neglect any force by the air. The frictional force on the vehicle by the road
(a) is zero if the vehicle is moving with a non-uniform velocity
(b) is towards east if the vehicle is accelerating
(c) must be towards east
(d) must be towards west
Ans: (c)
112. Match the following lists
List I List II
A. Static friction 1. is slightly less than limiting friction
B. Dynamic friction 2. is maximum value of static friction
C. Limiting friction 3. is equal to tangent of angle of repose
D. Coefficient of friction 4. is self- adjusting
Codes A B C D A B C D
(a) 2 3 4 1 (b) 4 1 2 3
(c) 3 2 1 4 (d) 4 1 3 2
Ans: (b)
113. Assertion (A) When a bicycle is in motion, the force of friction exerted by the ground on the two wheels is always in forward direction.
Reason (R) The frictional force acts only when the bodies are in contact.
(a) Both A and R are correct and R is true explanation of A
(b) Both A and R are correct but R is not true explanation of A
(c) A is correct and R is wrong
(d) A is wrong and R is correct
Ans: (b)
114. Assertion (A) On a rainy day, it is difficult to drive a car or bus at high speed.
Reason (R) The value of coefficient of friction is lowered due to wetting of the surface.
(a) Both A and R are correct and R is true explanation of A
(b) Both A and R are correct but R is not true explanation of A
(c) A is correct and R is wrong
(d) A is wrong and R is correct
Ans: (a)
115. Assertion (A) The value of dynamic friction is less than the limiting friction.
Reason (R) Once the motion has started, the inertia of rest has been overcome.
(a) Both A and R are correct and R is true explanation of A
(b) Both A and R are correct but R is not true explanation of A
(c) A is correct and R is wrong
(d) A is wrong and R is correct
Ans: (b)
116. Assertion (A) Pulling a lawn roller is easier than pushing it.
Reason (R) Pushing increases the apparent weight and hence the force of friction.
(a) Both A and R are correct and R is true explanation of A
(b) Both A and R are correct but R is not true explanation of A
(c) A is correct and R is wrong
(d) A is wrong and R is correct
Ans: (a)
117. Consider the following statements
1. Static force of friction is greater than kinetic or sliding force of friction.
2. Rolling force of friction is less than kinetic or sliding force of friction. Which of two statement (s) given above is/are correct?
(a) Only 1 (b) Only 2
(c) Both 1 and 2 (d) Neither 1 nor 2
Ans: (c)
118. Roadways are banked on curves so that
(a) the frictional force between the road and vehicle may be decreased
(b) the wear and tear of tyre may be avoided
(c) the speeding vehicles may not fall inwards
(d) the weight of the vehicle may be decreased
Ans: (a)
Part 5. Gravitation
119. The weight of the body at the centre of the earth is
(a) infinite (b) zero
(c) slightly less than at the equator
(d) slightlymore than that at the equatior
Ans: (b)
120. If the radius of the earth was shrink by one per cent, mass remaining the same, the value of g on the earth’s surface would
(a) increase by 0.5%
(b) increase by 2%
(c) decrease by 0.5%
(d) decrease by 2%
Ans: (d)
121. Two satellite are moving in the same circular orbit around the earth, they must have the same
(a) mass
(b) angular momentum
(c) KE (d) speed
Ans: (b)
122. Weightlessness experienced in spaceship is due to
(a) absence of inertia
(b) absence of accelerating force
(c) absence of gravity
(d) free fall of the spaceship
Ans: (c)
123. Consider the following statements The escape velocity depends on
1. radius of the planet.
2. temperature of the planet.
3. mass of the planet.
4. mass of the particles escaping. Select the correct answer from the codes given below.
(a) 1 and 2 (b) 1 and 3
(c) 1, 2 and 3 (d) 1, 2, 3 and 4
Ans: (b)
124. A man weighing 70 kg is coming down in lift. If the cable of the lift breaks sudden the weight of the man would become
(a) 70 kg (b) 35 kg
(c) 140 kg (d) Zero
Ans: (d)
125. Suppose the force of gravitation between two bodies of equal masses is
F. If each mass is doubled keeping the distance of separation between them unchanged, the force would become
(a) F (b) 2F
(c) 4F (d) 1/4 F
Ans: (b)
126. The ratio of the inertial mass to gravitational mass is equal to
(a) 1/2
(b) 2
(c) 1 (d) None of these
Ans: (c)
127. If the distance between two masses is doubled, the gravitational attraction between them
(a) is doubled
(b) is reduced to half
(c) becomes four times
(d) is reduced to quarter
Ans: (b)
128. The orbital speed of Jupiter is
(a) greater than the orbital speed of the earth
(b) less than the orbital speed of the earth
(c) zero
(d) equal to the orbital speed of the earth
Ans: (a)
129. Mass of a particular amount of substance
1. is the amount of matter present in it.
2. does not vary from place to place.
3. changes with change in gravitational force. Select the correct answer using the codes given below :
(a) 1, 2 and 3 (b) 1 and 2
(c) 2 and 3 (d) Only 1
Ans: (b)
130. Match the following lists
List I List II
A. Weight of a body is maximum 1. With increase in height from the surface of earth
B. Weight of a body decreases 2. Null point
C. Weight of a body increases 3. At the surface of earth
D. Weight of the body is zero 4. When body is moved from null point towards moon
Codes A B C D A B C D
(a) 1 2 3 4 (b) 4 3 2 1
(c) 3 1 4 2 (d) 3 4 1 2
Ans: (c)
131. During solar eclipse,
(a) the Earth comes in between the Sun and the Moon
(b) the Moon comes in between the Sun and the Earth
(c) the Moon comes exactly halfway between the Earth and the Sun
(d) the Sun comes in between the Earth and the Moon
Ans: (b)
132. Which one of the following is not a form of stored energy?
(a) Nuclear energy
(b) Potential energy
(c) Electrical energy
(d) Chemical energy
Ans: (a)
133. If the Earth was stop rotating, the value of g
(a) increases
(b) decreases
(c) remain unchanged
(d) becomes zero
Ans: (a)
134. Planet A has double the radius than that of Planet B. If the mass of Planet A is 4 times heavier than the mass of Planet B, which of the following statements regarding weight of an object is correct?
(a) Heavier on Planet A than on Planet B
(b) Heavier on Planet B than on Planet A
(c) Same on both the planets
(d) Cannot be measured on Planet B
Ans: (c)
135. A geostationary satellite should be launched such that it moves from
(a) South to North in the polar plane
(b) North to South in the polar plane
(c) West to East in the equatorial plane
(d) East to West in the equatorial plane
Ans: (c)
136. Consider the following statements The acceleration due to earth’s gravity decreases if
1. we go up from the surface of the earth.
2. we go from the equator towards the pole.
3. the rotation speed of the earth is increased.
4. we go down from the surface of the earth towards its centre.
Which of these statements are correct?
(a) 1, 2 and 3 (b) 1, 3 and 4
(c) 1, 2 and 4 (d) 1, 2, 3 and 4
Ans: (b)
137. A satellite revolves around the earth in elliptical orbit, its speed is
(a) greatest when it is farthest from the earth
(b) same at all points on the orbit
(c) greatest when it is closest to the earth
(d) None of the above
Ans: (b)
138. The Earth revolves around the sun in one year. If the distance between them becomes double, the new period of revolution will be
(a) 4 yr (b) 8 yr
(c) 1/2 yr (d) 22 yr
Ans: (b)
139. Consider the following statements
1. The time period of satellite does not depend on the radius of the orbit.
2. The orbital velocity is inversely proportional to the square root of the radius of the orbit.
3. The orbital velocity of a satellite increases with the radius of the orbit.
Which of the statement(s) given above is/are correct?
(a) Only 1 (b) Only 2
(c) 1 and 2 (d) 1, 2 and 3
Ans: (b)
140. Which of the following statements is true?
(a) g is the same at all places on the surface of the earth
(b) g is less at the earth’s surface than at a height above or at a depth below it
(c) g has its maximum value at the equator
(d) g is greater at the poles than at the equator
Ans: (a)
141. A man inside an artificial satellite feels weightlessness because the force of attraction due to earth is
(a) zero
(b) is balanced by the force of attraction due to moon
(c) equal to centrifugal force
(d) non-effective due to particular design of the satellite
Ans: (a)
142. Gravitational force shares a common feature with electromagnetic force. In both cases, the force is
(a) between massive and neutral objects
(b) between charged objects
(c) a short range
(d) a long range
Ans: (a)
143. A satellite revolves around the earth in a circular orbit. If gravitational pull suddenly disappear, then it
(a) falls down with increasing speed
(b) continues to move with the same speed and along the same path
(c) moves with the same speed tangential to the original orbit
(d) comes to rest after moving a certain distance along the original path
Ans: (c)
144. The given figure represents the time-velocity graph of a moving body. How much distance does the body cover?
(a) 20 m (b) 30 m
(c) 40 m (d) 50 m
Ans: (d)
145. Consider following statements
1. At the latitude of 45° and at the sea level the standard value of g is 9.8 m/ s2 or 32 ft / s2.
2. The value of g is not constant and varies from place to place.
Which of the statement(s) given above is/are correct?
(a) Only 1 (b) Only 2
(c) Both 1 and 2 (d) Neither 1 nor 2
Ans: (c)
146. Statement I Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon and the Sun and the rotation of the Earth.
Statement II Earth rotates from the West towards the East once in 24 hours with respect to the Sun.
Codes
(a) Statement I is correct.
(b) Statement II is correct.
(c) Both statments are correct.
(d) Both statements are incorrect.
Ans: (b)
147. The scientist who first discovered that the Earth revolves round the Sun was
(a) Newton (b) Dalton
(c) Copernicus (d) Einstein
Ans: (c)
148. A body is dropped from a height of 1000 m. At what height the velocity of the body will be equal to one half the velocity, when it hits the ground?
(a) 75 m (b) 65 m (c) 55 m (d) 45 m
Ans: (a)
149. Assertion (A) The graph between P and Q is a straight line, when P/Q /constant.
Reason (R) The straight line graph means that P Q or P /constant Q.
(a) Both A and R are individually true and R is the correct explanation of A
(b) Both A and R are individually true but R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
Ans: (a)
150. Consider the following statements
1. According to Kepler’s first law, each planet moves in an elliptical orbit around the sun, the sun being at one of the foci of the ellipse.
2. According to Kepler’s second law, the radius vector of any planet relative to the sun sweeps out equal areas in equal times, that is the areal velocity of the radius vector of the planet is constant.
Which of the statements given above is/are correct?
(a) Only 1 (b) Only 2
(c) Both 1 and 2
(d) Neither 1 nor 2
Ans: (c)
151. Assertion (A) The centripetal forces and centrifugal forces never cancel out.
Reason (R) They do not act at the same time.
(a) Both A and R are individually true and R is the correct explanation of A
(b) Both A and R are individually true but R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
Ans: (c)
152. Assertion (A) Distance travelled in a particular second has the dimension of distance.
Reason (R) Distance/Time /Velocity
(a) Both A and R are individually true and R is the correct explanation of A
(b) Both A and R are individually true but R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
Ans: (d)
153. If the radius of the earth’s orbit becomes one-fourth of the present value, the deviation of one year will become
(a) 8 times (b) 1/8 times
(c) 4 times (d) 1/4 times
Ans: (b)
154. For a missile launched with a velocity less than the Earth’s escape velocity, the total energy is
(a) positive
(b) negative
(c) zero
(d) Either positive or negative
Ans: (c)
155. The mass of a body on earth is 100 kg (acceleration due to gravity, g /10 m/ s2). If acceleration due to gravity on the moon is g/6 , then the mass of the body on the moon is
(a) 100/6 kg (b) 60 kg
(c) 100 kg (d) 600 kg
Ans: (c)
156. Newton’s laws of motion do not hold good for objects
(a) at rest
(b) moving slowly
(c) moving with high velocity
(d) moving with velocity comparable to velocity of light
Ans: (d)
157. Match the following lists
List I List II
A. Formation of day and night 1. Geostationary satellite
B. Short range warning about environment 2. Polar satellite
C. Longer term forecasting about environment 3. Rotation of earth around the sun
D. Formation of tide in ocean 4. Gravitational attraction between moon and ocean water
Codes A B C D A B C D
(a) 1 2 3 4 (b) 3 1 2 4
(c) 4 3 2 1 (d) 3 4 2 1
Ans: (b)
158. Consider the following statements
1. Geostationary satellites are used to reflect TV signals and telecast TV programmes from one part of the world to another.
2. Polar satellites are used for weather forecasting.
Which of the statements given above is/are correct?
(a) Only 1
(b) Only 2
(c) Both 1 and 2
(d) Neither 1 nor 2
Ans: (a)
159. Match the following lists
List I List II
A. Every planet revolves around the sun in elliptical orbit and the sun is situated at one foci of ellipse 1. Copernicus
B. The position vector of the particle with respect to the centre of force has a constant areal velocity 2. Ptolemy
C. Geocentric theory of planetary motion 3. Inverse square law
D. Heliocentric theory of planetary motion 4. Law of conservation of angular momentum
Codes A B C D A B C D
(a) 3 4 2 1 (b) 1 2 3 4
(c) 4 3 2 1 (d) 2 1 3 4
Ans: (a)
Part 6. Simple Harmonic Motion (SHM)
160. Consider the following statements
1. When a satellite is orbiting in its orbit, no energy is required to keep it in its orbit.
2. When the total energy of a satellite is negative, it will be moving in either a circular or an elliptical orbit.
3. When the total energy of a satellite is zero, it will escape away from its orbit and its path becomes parabolic.
4. When the total energy of a satellite is positive, it will escape away from the orbit following a hyperbolic path.
Which of the statement(s) given above are correct?
(a) 1, 2 and 3 (b) 1, 3 and 4
(c) 2, 3 and 4 (d) 1, 2, 3, 4
Ans: (c)
161. For a harmonic oscillator, the graph between momentum p and displacement q would come out as
(a) a straight line (b) a parabola
(c) a circle (d) an ellipse
Ans: (b)
162. For a satellite moving in an orbit around the earth, the ratio of kinetic energy to potential energy is
(a) 1/2 (b) 1/2
(c) 2 (d) 2
Ans: (b)
163. When a particle executing in SHM passes through themean position it has
(a) maximum KE and minimum PE
(b) maximum KE and maximum PE
(c) minimum KE and minimum PE
(d) minimum KE and maximum PE
Ans: (a)
164. A particle is executing in SHM. Then the graph of acceleration as a function of displacement is
(a) straight line (b) ellipse
(c) hyperbola (d) circle
Ans: (b)
165. A simple pendulum is oscillating in a lift. If the lift starts moving upwards with a uniform acceleration, the period will
(a) be longer
(b) remain unaffected
(c) be shorter
(d) None of the above
Ans: (c)
166. The restoring force in SHM is maximum, when the particle is
(a) half way between mean position and the extreme position
(b) rest initially
(c) at rest instantaneously
(d) at mean position
Ans: (c)
167. A simple pendulum is vibrating in an evacuated chamber. It will
(a) come to rest eventually
(b) oscillate with the same amplitude but frequency will decrease with time
(c) oscillate with same frequency but amplitude will decreases with time
(d) oscillate for ever with the same amplitude and frequency
Ans: (d)
168. A simple harmonic oscillator has time period T. The time taken by it to travel from the extreme position to half the amplitude is
(a) T/6
(b) T/3
(c) T/4
(d) T/2
Ans: (c)
169. Consider the following statements about periodic motion
1. Any motion that repeats in equal intervals of time is called a periodic motion.
2. The motion of the earth about its axis is a periodic motion.
3. The motion of the position of an engine, the motion of a pendulum, the motion of an electron in an atom
etc. are the examples of periodic motion.
Which of the statement(s) given above is/are correct?
(a) Only 1 (b) Only 2
(c) 1 and 2 (d) 1, 2 and 3
Ans: (c)
170. Assertion (A) A body moving in a circular path is acted upon by the centripetal force.
Reason (R) Centripetal force acting on the body is doing work to keep it rotating in the circular path.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true, but R is not the correct explanation of A.
(c) A is true, but R is false.
(d) A is false, but R is true.
Ans: (c)
171. If a pendulum clock is brought inside an artificial satellite, then the time period of the clock becomes
(a) 0 (b) (c) 1 (d) None of these
Ans: (b)
172. Consider the following statements
1. If an oscillator executing in SHM passes through a fixed point (mean position) then the potential energy of the oscillator is zero but the kinetic energy is maximum.
2. If an oscillator executing in SHM passes through the extreme (end point) then the oscillator instantaneously comes to rest (its velocity becomes zero) thus kinetic energy becomes zero. But its potential energy is maximum.
Which of the statement(s) given above is/are correct?
(a) Only 1
(b) Only 2
(c) Both 1 and 2
(d) Neither 1 nor 2
Ans: (c)
173. Consider the following statements
1. On increasing the length of the pendulum, the time period of pendulum will increase.
2. The time period of a simple pendulum doesn’t depend upon its mass.
Which of the statement(s) given above is/are correct?
(a) Only 1
(b) Only 2
(c) Both 1 and 2
(d) Neither 1 nor 2
Ans: (a)
174. If a pendulum clock is brought on the moon, then the period of oscillation of the pendulum clock becomes
(a) decreased (b) increased
(c) zero (d) infinite
Ans: (b)
175. The displacement (x)-time (t) graph given above approximately represents the motion of a
(a) simple pendulum placed in vacuum
(b) simple pendulum immersed in water
(c) simple pendulum placed in outer space
(d) point mass moving in air
Ans: (b)
176. Consider the following statements
1. In summer season, the effective length of the pendulum clock is lengthened (increased length), so its time period is also increased and consequently the clock becomes slow.
2. In winter season, the effective length is contracted thus time period is decreased and the clock becomes fast.
Which of the statement(s) given above is/are correct?
(a) Only 1 (b) Only 2
(c) Both 1 and 2
(d) Neither 1 nor 2
Ans: (c)
Part 7. Properties of Matter
177. The pressure in a liquid at a given depth below the surface
(a) is same in all directions
(b) is always exerted downward
(c) equals the total weight of liquid above the depth
(d) depends upon the amount of liquid below the depth
Ans: (a)
178. It is difficult to cut things with a blunt knife because
(a) the pressure exerted by knife for a given force increases with increase in bluntness
(b) a sharp edge decreases the pressure exerted by knife for a given force
(c) a blunt knife decreases the pressure for a given force
(d) a blunt knife decreases the area of intersection
Ans: (c)
179. The pressure of the earth’s atmosphere at sea level is due to the
(a) heating of the atmosphere by the sun
(b) fact that most living things constantly breathe air
(c) evaporation of water from the seas and oceans
(d) gravitational attraction of the earth for the atmosphere
Ans: (d)
180. The pressure at the bottom of a liquid tank does not depend on
(a) density of the liquid
(b) acceleration due to gravity
(c) area of the liquid surface
(d) height of the liquid
Ans: (c)
181. An inflated balloon rises to a definite height once it starts going up. This balloon cannot rise any further because at that height
(a) atmospheric pressure reduces to zero
(b) apparent weight of the balloon reduces to zero
(c) density of the balloon reduces to zero
(d) acceleration due to gravity reduces to zero
Ans: (b)
182. The rate of leak from a hole in a tank is
(a) more if situated near the bottom
(b) more if situated near its top
(c) independent of its height from the bottom
(d) more at mid way between top and bottom
Ans: (a)
183. If we want to calculate the pressure of a liquid at the bottom of vessel, the quantity which is not required to determine it, is
(a) surface area of the bottom of the vessel
(b) height of the liquid column
(c) density of the liquid
(d) acceleration due to gravity at the bottom of the vessel
Ans: (a)
184. An ideal liquid flows through a horizontal tube of variable diameter. The pressure is lowest where the
(a) velocity is lowest
(b) velocity is highest
(c) diameter is largest
(d) None of the above
Ans: (b)
185. Consider the following statements
1. The boiling point of a liquid increases on increasing the pressure on the free surface of the liquid.
2. On heating the solid substance if the volume of the substance increases, then by the application of pressure its melting point increases.
Which of the statement(s) given above is/are correct?
(a) 1 and 2 (b) Only 1
(c) Only 2 (d) Neither 1 nor 2
Ans: (a)
186. Consider the following statements
1. At any point inside the liquid the pressure exerted by the liquid is directly proportional to its depth from the free surface.
2. At every point and in every direction, the pressure exerted inside the liquid at rest is same.
Which of the statement(s) given above is/are correct?
(a) Only 1 (b) Only 2
(c) Both 1 and 2 (d) Neither 1 nor 2
Ans: (c)
187. The densities of three liquids are D, 2D and 3D. What will be the density of the resulting mixture if equal volumes of the three liquids are mixed?
(a) 6 D
(b) 1.4 D
(c) 2 D (d) 3 D
Ans: (c)
188. Consider the following statements
1. The liquid pressure is inversely proportional to the density of liquid.
2. The pressure exerted on the liquid doesn’t depend upon the shape or size of the container.
Which of the statement(s) given above is/are correct?
(a) Only 1
(b) Only 2
(c) Both 1 and 2
(d) Neither 1 nor 2
Ans: (b)
189. Pressure at any point of a liquid increases with
(a) density of the liquid
(b) acceleration due to gravity
(c) depth of the point fromthe free surface
(d) All of the above
Ans: (d)
190. An iron piece and a wooden piece have equal weights in air. If they are removed from air to vacuum
(a) the wooden piece appears to weight more
(b) the iron piece appears to weight more
(c) there is no change in the weight of either
(d) None of the above
Ans: (a)
191. Which one of the following is used by the mountaineers and the pilots to measure pressure?
(a) Simple barometer
(b) Fortin barometer
(c) Manometer
(d) Aneroid barometer
Ans: (d)
192. Consider the following statements and select the correct code
1. Manometer is a device for measuring differences in pressure usually by noting the difference in the height of two liquid columns.
2. Sphygmomanometer is a device used to measure blood pressure.
Codes
(a) Only 1 (b) Only 2
(c) 1 and 2 (d) Neither 1 nor 2
Ans: (c)
193. Consider the following statements
1. Those substances, which expand on freezing have their melting point lowered by the increase of pressure, where as those substances which contract on freezing have their melting points raised by the increase of pressure.
2. The phenomenon that ice melts on application of pressure and again solidifies when the pressure is released is known as regelation.
Which of the statement(s) given above is/are correct?
(a) Only 1 (b) Only 2
(c) Both 1 and 2 (d) Neither 1 nor 2
Ans: (c)
194. Density of water is
(a) maximum at 0°C
(b) minimum at 0°C
(c) maximum at 4°C
(d) minimum at –4°C
Ans: (c)
195. Why do two ice blocks join to form one block when pressed together?
(a) Melting point of ice is lowered with increase in pressure
(b) Melting point of ice increases with increase in pressure
(c) Melting point of ice remains unchanged with increase in pressure
(d) Melting point of ice is 0°C
Ans: (a)
196. Consider the following statements An external pressure p0 is applied to the surface of liquid in a container. Then,
1. The pressure on all side walls increase by p0.
2. The pressure on the bottom wall increased by p0.
3. The pressure at all points inside the liquid increases by p0.
Which of the statement(s) given above is/are correct?
(a) 1, 2 and 3 (b) 1 and 2
(c) 1 and 3 (d) 2 and 3
Ans: (c)
197. Consider the following statements
1. SI unit of atmospheric pressure is Nm –2 or pascal and CGS unit is dyne / cm2.
2. The barometer is a device by which the atmospheric pressure is measured.
3. The standard atmospheric pressure is the pressure required of 76 cm of Hg column or 760 mm of Hg column, which is equivalent to 1 atm.
Which of the statements given above is/are correct?
(a) 1 and 2
(b) Only 1
(c) 2 and 3
(d) 1, 2 and 3
Ans: (d)
198. Assertion (A) When water flows in a uniform horizontal pipe, there is a fall in pressure of water along the pipe.
Reason (R) Force is required to maintain the motion of the liquid against friction code.
(a) Both A and R are individually true and R is the correct explanation of A
(b) Both A and R are individually true but R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
Ans: (a)
Part 8. Floatation
199. A block of ice is floating in a glass containing water. When the ice melts completely, the level of the water in the glass will
(a) rise (b) fall
(c) not change
(d) None of the above
Ans: (c)
200. The principle of cleaning by soap is
(a) surface tension (b) floatation
(c) viscosity (d) elasticity
Ans: (a)
201. For a body float in a liquid with some portion outside, the weight of the liquid displaced by the fully immersed body
(a) should be more than the weight of the body
(b) should be equal to the weight of the body
(c) should be less than the weight of the body
(d) None of the above
Ans: (a)
202. It is easier to swim in a sea water than in ordinary water because
(a) sea water contains salt
(b) atmospheric pressure is highest at the sea level
(c) density of sea water is less than that of ordinary water
(d) density of sea water is higher than that of ordinary water
Ans: (d)
203. A steel ball is floating in a beaker containing mercury. If some water is poured in the breaker, the steel ball will
(a) move up (b) move down
(c) continue its position
(d) execute vertical oscillation
Ans: (a)
204. Two pieces of different metals, when completely immersed in water, experience equal upthrust, then
(a) both pieces have same density
(b) both pieces have equal volume
(c) both pieces have equal weight in air
(d) None of the above
Ans: (b)
205. A body is just floating in a liquid if the body is slightly pressed down and released. It will
(a) start oscillating
(b) sink to the bottom
(c) come back to the same position immediately
(d) come back to the same position stable
Ans: (b)
206. An inflated balloon is floating on the surface of water. It is pushed so as to submerge completely and then released. It will
(a) sink to the bottom
(b) come back to its earlier position
(c) remain submerged at the same place
(d) first sink to the bottom and then come up
Ans: (b)
207. Consider the following statements When an object floats inside a liquid, then
1. The apparent weight of the object is equal to the liquid displaced by the object.
2. The centre of gravity (CG) of the object and the centre of gravity (CG) of the displaced water lie in the same vertical line.
Which of the above statement(s) given above is/are correct?
(a) Only 1 (b) Only 2
(c) Both 1 and 2 (d) Neither 1 nor 2
Ans: (c)
208. In order that a floating object be in stable equilibrium, its centre of buoyancy
(a) should be vertically below its centre of gravity
(b) should be horizontal in line with its centre of gravity
(c) should be vertically above its centre of gravity
(d) may be anywhere
Ans: (c)
209. Assertion (A) The ships of iron and the boats of wood float in water but the nails iron sink.
Reason (R) The special design and shape of the ship and the boat through which weight of displaced water are more than the weight of the ship and boat, due to which more force of buoyancy becomes operative and the ships or boats floats. But the weight of the water displaced by the nails is less than the weight of nails that is why nails sink.
(a) Both A and R are individually true, but R is the correct explanation of A
(b) Both A and R are individually true and R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
Ans: (a)
210. Consider the following statements The fraction of a ball floating inside the liquid depends upon
1. density of the liquid
2. mass of the ball
3. density of the ball
Which of the statements given above are correct?
(a) 1 and 2 (b) 2 and 3
(c) 1 and 3 (d) 1, 2 and 3
Ans: (c)
Part 9. Surface Tension
211. Consider the following statements
1. Surface tension of liquid depends on length but not on the area, like the elastic property.
2. SI unit of surface tension is N/m.
3. Surface tension is a scalar quantity because it has no specific direction for a given liquid.
Which of the statement(s) given above is/are correct?
(a) 1 and 2 (b) Only 3
(c) 2 and 3 (d) 1, 2 and 3
Ans: (d)
212. Surface tension depends on
(a) atmospheric pressure
(b) nature of the liquid
(c) temperature of the liquid
(d) All of the above
Ans: (d)
213. With the rise of temperature, the surface tension of a liquid
(a) increases (b) decreases
(c) remains unchanged
(d) None of the above
Ans: (b)
214. Two capillary tubes of different diameters are dipped in water. The rise of water is
(a) same in both tubes
(b) greater in the tube of smaller diameter
(c) greater in the tube of larger diameter
(d) None of the above
Ans: (b)
215. Kerosene oil rises up in the wick of lantern because of
(a) surface tension
(b) buoyant force of air
(c) diffusion of the oil through the wick
(d) the gravitational pull of the wick
Ans: (a)
216. Insects can move on the surface of water without sinking due to
(a) viscosity of water
(b) surface tension of water
(c) Both (a) and (b)
(d) None of the above
Ans: (b)
217. When some detergent is added to water, the surface tension
(a) increases (b) remains unaffected
(c) decreases (d) None of these
Ans: (c)
218. The excess of pressure inside a dropper bubble is
(a) directly proportional to its radius
(b) inversely proportional to its surface tension
(c) directly proportional to its mass
(d) inversely proportional to its radius
Ans: (d)
219. A liquid drop tends to assume a spherical shape because of
(a) surface tension (b) elastic force
(c) gravitational force (d) viscous force
Ans: (a)
220. If a liquid wets a solid surface, the angle of contact is
(a) 0°C (b) less than 90°
(c) greater than 90° (d) 90°
Ans: (b)
221. The surface tension phenomenon is the result of the tendency of a system to
(a) conserve volume
(b) keep surface area minimum
(c) keep potential energy minimum
(d) conserve energy
Ans: (b)
222. Water drops do not stick to the oily surface due to
(a) lack of adhesive force
(b) surface tension
(c) cannot mix each other
(d) water is lighter than oil
Ans: (a)
223. Which of the following curves represents the variation of surface tension (Y) with temperature (T)?
Ans: (d)
224. A liquid will not wet the surface of solid if the angle of contact is
(a) obtuse (b) acute
(c) 2 (d) zero
Ans: (a)
225. An oil drop is placed on the surface of water. It will
(a) remain on the surface as a distorted drop
(b) remain on the surface as a sphere
(c) spread as a thin layer
(d) None of the above
Ans: (c)
226. Meniscus of mercury in a capillary is
(a) plane (b) cylindrical
(c) concave (d) convex
Ans: (d)
227. When there is no external force, the shape of a liquid drop is determined by
(a) viscosity of air
(b) density of the liquid
(c) temperature of air
(d) surface tension of the liquid
Ans: (d)
Part 10. Viscosity
228. When the temperature increases, the angle of contact of liquid
(a) decreases (b) increases
(c) remain the same (d) None of these
Ans: (a)
229. Consider the following statements
1. Venturimeter is an instrument and is based upon Bernoulli’s theorem by which the rate of flow of the liguid is measured through a pipe.
2. Pitot tube is an instrument and is based upon Bernoullis theorem by which the rate of flow of the gas is measured.
Which of the statement(s) given above is/are correct?
(a) Only 1 (b) Only 2
(c) Both 1 and 2 (d) Neither 1 nor 2
Ans: (c)
230. Ball pen functions on which one of the following principle?
(a) Boyle’s law
(b) Gravitational force
(c) Surface tension
(d) Viscosity
Ans: (c)
231. Bernoulli’s theorem is based on the conservation of
(a) energy (b) mass
(c) momentum (d) All of these
Ans: (a)
232. Viscosity is the property of liquids by virtue of which they
(a) attract other molecules
(b) become conducting
(c) oppose the relativemotion of its parts
(d) push neighbouring molecules
Ans: (c)
233. If temperature rises, the coefficient of viscosity of liquid
(a) increases (b) decreases
(c) remains unchanged
(d) None of these
Ans: (b)
234. A solid ball of volumeV is dropped in a viscous liquid. It experiences a viscous force F. If the solid ball of volume 2V of the same material is dropped in the same fluid, then the viscous force acting on it will be
(a) 2F (b) 2nF (c) F/2
(d) n F/2
Ans: (a)
235. When the terminal velocity is reached, the acceleration of a body moving through a viscous medium is
(a) negative (b) positive
(c) zero (d) None of these
Ans: (c)
236. Bernoulli’s theorem is applicable to
(a) surface tension (b) viscosity
(c) flow of liquids
(d) static fluid pressure
Ans: (c)
237. The terminal velocity of a small sized spherical body of radius r falling in a viscous liquid is proportional to
(a) 1/r2
(b) 1/r
(c) r2 (d) r
Ans: (c)
238. An application of Bernoulli’s equation for fluid flows is found in
(a) viscosity meter (b) capillary rise
(c) hydraulic press
(d) dynamic lift of an aeroplane
Ans: (c)
239. A small drop falls from rest from a large height h in air the final velocity is
(a) almost independent of h
(b) directly proportional to h
(c) inversely proportional to h
(d) directly proportional to h2
Ans: (a)
240. A small and a large rain drops are falling through air
(a) the small drop moves faster
(b) the large drop moves faster
(c) both moves with same speed
(d) None of the above
Ans: (c)
241. Consider the following statements. The rise of a liquid in a capillary tube depends on
1. The moment
2. The length
3. The outer radius
4. The inner radius of the tube
Which of the following statements is/are true?
(a) 1, 2 and 4 (b) 1 and 2
(c) 1 and 4 (d) 2 and 4
Ans: (a)
242. Three identical vessels A, B and C are filled with water, mercury and kerosene respectively up to a equal height. The three vessels are provided with identical taps at the bottom of the vessels. If the three taps are opened simultaneously, then which vessel is emptied first?
(a) Vessel B
(b) All the vessels A, B and C will be emptied simultaneously
(c) Vessel A
(d) Vessel C
Ans: (d)
243. Consider the following statements
1. The viscosity of a gas increases with rise in temperature.
2. The viscosity of the liquid falls very rapidly with rise in temperature.
Which of the statements (s) given above is/are correct?
(a) Only 1 (b) Only 2
(c) Both 1 and 2 (d) Neither 1 nor 2
Ans: (c)
244. The velocity of flow of liquid through an orifice at the bottom of a tank depends on the
(a) height of the liquid above the orifice
(b) acceleration due to gravity
(c) area of the cross-section of the orifice
(d) Both a and b
Ans: (d)
245. A large tank having a small hole at the bottom is filled with water to a height h. If the stream of water coming out of the hole is directed vertically upwards it will
(a) rise to a height less than h
(b) rise to height h
(c) rise to height greater than h
(d) Not rise at all
Ans: (b)
246. Assertion (A) The viscosity increases with the temperature
Reason (R) The increase in temperature increases the internal energy of the molecules
(a) Both A and R are correct and R is the reason of A
(b) Both A and R are correct, but R is not the reason of A
(c) A is correct, but R is incorrect
(d) A is incorrect and R is correct
Ans: (d)
Part 11. Elasticity
247. The figure given above shows the stress-strain relationship in a wire. In the figure, the point A corresponds to
(a) elastic limit (b) breaking point
(c) yield point (d) proportional limit
Ans: (d)
248. If two conducting spheres are separately charged and then brought in contact
(a) the total energy of the two spheres is conserved
(b) the total charge on the two spheres is conserved
(c) both the total energy and the total charge are conserved
(d) the final potential is always the mean of the original potential of the two spheres
Ans: (b)
249. The Young’s modulus for perfectly rigid body is
(a) zero (b) 1
(c) infinite (d) None of these
Ans: (c)
250. Which among the following figure shows the variation of stress and strain for a vulcanized rubber?
Ans: (b)
251. Consider the following statements and select the correct code
1. For a given stress, the strain produced in glass is much less than that in rubber.
2. In plastic materials, the force of cohesion are very small.
3. Elastic limit is the smallest stress, which results in permanent distortion.
Codes
(a) 1, 2 and 3 (b) 1 and 2
(c) 2 and 3 (d) 1 and 3
Ans: (a)
252. The modulus of rigidity of a liquid is
(a) zero (b) infinite
(c) 1 (d) None of these
Ans: (a)
253. Assertion (A) The solids are more elastic and gases are least elastic.
Reason (R) It is so because for the given stress applied the gases are more compressible than that of solids.
Codes
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true and R is not the correct explanation of A
(c) A is true, but R is false
(d) A is false, but R is true
Ans: (a)
254. Consider the following statements
1. Greater the value of Young’s modulus of a material, larger is its elasticity.
2. Steel is more elastic than copper.
Which of the statement(s) given above is/are correct?
(a) Only 1
(b) Only 2
(c) Both 1 and 2
(d) Neither 1 nor 2
Ans: (c)
255. Consider the following statements
1. The SI unit of Young’s modulus of elasticity is Nm –2 or pascal.
2. Young’s modulus is involved in solids only.
3. The SI unit of Bulk modulus of elasticity is Nm –2 or pascal.
4. Bulk modulus is involved in solids, liquids and gases.
Which of the statements given above are correct?
(a) 1, 2 and 3 (b) 2, 3 and 4
(c) 1, 3 and 4 (d) 1, 2, 3 and 4
Ans: (d)
256. Consider the following statements
1. Young’s modulus of elasticity is defined as the ratio of normal stress to the longitudinal strain within the elastic limit.
2. Bulk modulus of elasticity is defined as the ratio of normal stress to the volumetric strain, within the elastic limit.
Which of the statement(s) given above is/are correct?
(a) Only 1 (b) Only 2
(c) Both 1 and 2 (d) Neither 1 nor 2
Ans: (c)
257. Consider the following statements
1. Quartz and phosphor or bronze are the examples of nearly perfectly elastic bodies.
2. Putty, mud and paraffin wax are the examples of perfectly plastic bodies.
Which of the statement(s) given above are correct?
(a) Only 1 (b) Only 2
(c) Both 1 and 2 (d) Neither 1 nor 2
Ans: (c)
258. Consider the following statements
1. Modulus of rigidity or shear modulus of elasticity (G) is defined as the ratio of tangential stress to the shearing strain, within the elastic limit.
2. The SI unit of modulus of rigidity is Nm –2 or pascal.
3. Modulus of rigidity is involved with solids only.
Which of the statement(s) given above is/are correct?
(a) 1, 2 and 3 (b) 2 and 3
(c) 1 and 3 (d) 1 and 2
Ans: (a)
259. The SI unit of elastic potential energy is
(a) watt (b) joule
(c) joule s (d) joule s-1
Ans: (b)
260. The breaking stress of wire depends on
(a) material of the wire
(b) length of the wire
(c) radius of the wire
(d) shape of the cross-section of the wire
Ans: (a)
261. Consider the following statements
1. If a body completely gains its original shape after removal of force, it is elastic body.
2. The property to restore the natural shape of a body is elasticity.
3. When a body partially reagains its original shape after removal of deforming force it is partially elastic. Which one of the option is correct?
(a) 1 and 2 (b) 1 and 3
(c) 2 and 3 (d) All are correct
Ans: (d)
262. The elastic potential energy of a body is
1. Work done by the external force against the deforming force.
2. Work done against the external force by the deforming force.
3. The sum of work done by the external force and the deforming force. Which one option is true?
(a) Only 1 (b) 1 and 3
(c) 1, 2 and 3 (d) None of these
Ans: (a)
263. If by applying a force, the shape of a body is changed, then the corresponding stress is
(a) Tensile stress
(b) Bulk stress
(c) Shearing stress
(d) Compressive Stress
Ans: (c)
264. Elasticity in the material is due to
1. The change or effective radius of the molecules
2. The change in intermolecular distance and restoring forces starts acting on the molecules.
3. The deforming forces acting on it. Which option is true?
(a) 1 and 2 (b) 2 and 3
(c) 1, 2 and 3 (d) Only 2
Ans: (d)
265. Longitudinal strain is defined when
(a) under a large force change in length is smaller
(b) under a weak force change in length be smaller
(c) under a large force, change in length is larger
(d) None of the above
Ans: (a)
266. Consider the following statements
1. If a body completely gains its original shape after removal of forces, it is elastic body.
2. The property to restore the natural shape of a body is elasticity.
3. When a body partially regains its original shape after removal of deforming force it is partially elastic. Which one of the options is/are correct?
(a) 1 and 2 (b) 1 and 3
(c) 2 and 3 (d) All are correct
Ans: (d)
267. When deep sea fishes are brought to the surface of the sea, their bodies burst. This is because the blood in their bodies flows at very
(a) high speed
(b) high pressure
(c) low speed
(d) low pressure
Ans: (a)
268. In an experiment to determine the Young’s modulus of a material of a wire, and the suspended mass are doubled. Then the Young’s modulus of the wire.
(a) Becomes double
(b) Becomes four times
(c) Remain unchanged
(d) Becomes half
Ans: (c)
269. When ice melts, its
(a) volume decreases
(b) volume increases
(c) volume and mass both decrease
(d) volume decreases while mass increases
Ans: (a)
270. Assertion (A) Pulling a lawn roller is easier than pushing it.
Reason (R) Pushing increases the apparent weight and hence the force of friction.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true and R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
Ans: (a)
Part 12. Waves
271. Ultraviolet light of sun’s radiation is prevented from reaching the earth’s atmosphere by the layer of
(a) oxygen (b) hydrogen
(c) ozone (d) helium
Ans: (c)
272. The standing wave pattern along a string of length 60 cm is shown in the given diagram below. If the speed of the transverse waves on this string is 300 m/s, in which one of the following mades in the string vibrating?
(a) Fundamental (b) First overtone
(c) Second overtone
(d) Third overtone
Ans: (c)
273. Match List I (Frequency Range) with List II (Wave) and select the correct answer.
List I List II
A. 54 MHz to 890 MHz 1. Television waves
B. 1710 kHz to 54 MHz 2. Short wave
C. 88 MHz to 108 MHz 3. FM radio
D. 300 MHz to 3000 MHz 4. UHF band
Codes A B C D A B C D
(a) 1 2 3 4 (b) 4 3 2 1
(c) 3 4 2 1 (d) 2 1 3 4
Ans: (a)
274. Doppler effect is independent of
(a) velocity of source
(b) velocity of listener
(c) distance between source and observer
(d) None of the above
Ans: (c)
275. Sound wave cannot pass through above
(a) a solid-liquid mixture
(b) an ideal gas
(c) a liquid gas mixture
(d) a perfect vacuum
Ans: (d)
276. With the propagation of a longitudinal wave through a material medium, the quantities transferred in the direction of propagation are
(a) energy and momentum
(b) energy, momentum and mass
(c) energy and mass
(d) energy
Ans: (a)
277. Which one of the following statements is not correct?
(a) The velocity of sound in air is independent of pressure
(b) The velocity of sound in air increases with increase of temperature
(c) The velocity of sound in air decreases as the humidity increases
(d) The velocity of sound in air is not affected by the change in amplitude and frequency
Ans: (c)
278. When the same note is played on a sitar and a flute, the sound produced can be distinguished from each other because of the difference in
(a) pitch and loudness
(b) quality only
(c) pitch, loudness and quality
(d) loudness only
Ans: (b)
279. With the increase in temperature, the frequency of the sound from an organ pipe
(a) increases (b) decreases
(c) remain unchanged
(d) changes erractically
Ans: (c)
280. Ultrasonic waves are produced by
(a) Peltier’s effect
(b) Piezoelectric effect
(c) Doppler’s effect
(d) Coulomb’s law
Ans: (b)
281. Electromagnetic waves are produced by
(a) chargeless particle
(b) a static charge
(c) a moving charge
(d) an acceleration charge
Ans: (d)
282. The ratio of the speed of X-rays to that of gamma rays is
(a) <1
(b) >1
(c) 1
(d) depends upon the ratio of their frequencies
Ans: (c)
283. Which of the following electromagnetic waves has the longest wavelength?
(a) Infrared rays (b) Gamma rays
(c) Light rays (d) Ultraviolet rays
Ans: (a)
284. Which one of the following has highest frequency?
(a) Cosmic rays (b) X-rays
(c) Radiowaves (d) Microwaves
Ans: (a)
285. X-rays were discovered by
(a) Roentgen (b) Becquerel
(c) Curie (d) Van lane
Ans: (a)
286. X-rays are not used for radar purpose because
(a) they are completely absorbed by air
(b) they are not reflected by the target
(c) they are not electromagnetic wave
(d) None of the above
Ans: (b)
287. Consider the following parts of spectra
1. Visible 2. Infrared
3. Ultraviolet 4. Microwave Which one of the following is the correct sequence in which their wavelengths increase?
(a) 4-3-1-2 (b) 4-1-2-3
(c) 3-2-1-4 (d) 3-1-2-4
Ans: (d)
288. Which one of the following is not electromagnetic in nature?
(a) Cathode rays (b) X-rays
(c) Gamma rays (d) Infrared rays 60 cm
Ans: (a)
289. Who firstly demonstrated experimentally the existence of electromagnetic wave?
(a) Hertz (b) Romar
(c) Marconi (d) Maxwell
Ans: (d)
290. Electromagnetic waves can travel through
(a) a medium such as air and water
(b) space where there are no electric and magnetic fields
(c) electric field or magnetic field
(d) Both (a) and (b)
Ans: (d)
291. Match List I (Electromagnetic radiation) with List II (Approximate wavelength in metre) and select the correct answer using the codes given below the lists.
List I List II
A. Infrared radiation 1. 10 –12
B. X-rays 2. 10 –5
C. Ultraviolet radiation 3. 10 –10
D. Gamma rays 4. 10 –8
Codes A B C D A B C D
(a) 2 3 4 1 (b) 1 4 3 2
(c) 1 3 4 2 (d) 2 4 3 1
Ans: (a)
292. The patient is asked to drink barium sulphate (BaSO4) for examining the stomach by X-rays because X-rays are
(a) less absorbed by heavy atoms
(b) more absorbed by heavy atoms
(c) reflected by heavy atoms
(d) refracted by heavy atoms
Ans: (b)
293. Figure given shows the part of a long string in which waves are produced. Which pair of points is in same phase?
(a) A and E (b) B and J
(c) D and J (d) C and G
Ans: (b)
294. Consider the following statements
1. Light of longer wavelength is scattered much more than the light of shorter wavelength.
2. The speed of visible light in water is 0.95 times the speed in vacuum.
3. Radio waves are produced by rapidly oscillating electrical currents.
4. To detect the overspeeding vehicles, police use the Doppler effect of reflected short radiowaves.
Which of these statements are correct?
(a) 1 and 2 (b) 1 and 3
(c) 2 and 4 (d) 3 and 4
Ans: (d)
295. Ultrasonic waves are those waves which
(a) human beings can hear
(b) human beings cannot hear
(c) have high velocity
(d) have large amplitude
Ans: (b)
296. The audible frequency range of a human ear is
(a) 20 Hz to 200 Hz
(b) 2 Hz to 20 Hz
(c) 200 Hz to 2000 Hz
(d) 20 Hz to 2000 Hz
Ans: (d)
297. Transverse waves can propagate
(a) in a gas but not in a metal
(b) both in a gas and in a metal
(c) not in a gas but in a metal
(d) neither in a gas nor in a metal
Ans: (c)
298. With the rise of temperature, the speed of sound in a gas
(a) decreases (b) increases
(c) remains the same
(d) None of the above
Ans: (b)
299. SONAR is based on the principle of
(a) resonance (b) reveberation
(c) echo
(d) None of these
Ans: (c)
300. Which one of the following is the correct sequence of wavelengths of radiations?
(a) UV > Green > IR > Hard X-rays
(b) IR > Green > UV > Hard X-rays
(c) UV > Hard X-rays > IR > Green
(d) IR > Hard X-rays > Green > UV
Ans: (b)
301. What frequency range of EM waves are used for commercial FM radio?
(a) 88 MHz to 108 MHz
(b) 88 GHz to 108 GHz
(c) 88 kHz to 108 kHz
(d) None of the above
Ans: (a)
302. Polarization in electromagnetic wave is caused by
(a) refraction
(b) reflection
(c) transverse nature of electromagnetic waves
(d) longitudinal nature of electromagnetic waves
Ans: (c)
303. The wavelength of X-rays is of the order of
(a) 1 mm (b) 1 cm
(c) 1 micron (d) 1 angstrom
Ans: (d)
304. Why is sound heard with more intensity through CO2 than through the air?
(a) Density of CO2 is more than that of air
(b) Density ofCO2 is less than that of air
(c) Air is a bad conductor of heat
(d) CO2 is a compound but air is a mixture of gases
Ans: (a)
305. How does time period (T) of a second pendulum vary with length (l)?
(a) Tl
(b) Tl 2 (c) Tl
(d) T does not depend on l
Ans: (d)
306. Some common mediums in which speed of sound waves is measured are mentioned below.
1. Air 2. Steel
3. Copper 4.Water What is the correct increasing order of the speed of sound?
(a) 1 < 4 < 2 < 3 (b) 4 < 1 < 2 < 3
(c) 1< 4 < 3 < 2 (d) 4 < 1 < 3 < 2
Ans: (c)
307. Sound moves with higher velocity if
(a) pressure of themedium is decreased
(b) temperature of the medium is increased
(c) humidity of the medium
(d) Both (b) and (c)
Ans: (d)
308. Speed of electromagnetic wave is the same
(a) for all frequencies
(b) for all wavelengths
(c) in all media
(d) for all intensities
Ans: (d)
309. Consider the following statements
1. Microwave ovens are used for cooking purposes.
2. Microwaves are used in Radar system for aircraft navigation.
3. A radar using microwave can help in detecting the seed of tennis ball, cricket ball, automobile while in motion.
Which of the statements given above are correct?
(a) 2 and 3 (b) 1 and 2
(c) 1 and 3 (d) 1, 2 and 3
Ans: (d)
310. Radar waves are sent towards a moving aeroplane and the reflected waves are received. When the aeroplane is moving towards the radar, the wavelength of the wave
(a) decreases
(b) increases
(c) remains the same
(d) sometimes increases or decreases
Ans: (a)
311. Match List I (Electromagnetic Wave) with List II (Discoverer) and select the correct answer using the codes given below
List I List II
A. Infrared waves 1. Ritter
B. Ultraviolet rays 2. Newton
C. X-rays 3. Herchel
D. Visible rays 4. W.Roentgen
Codes A B C D A B C D
(a) 1 2 3 4 (b) 3 1 4 2
(c) 4 3 2 1 (d) 3 2 1 4
Ans: (b)
312. The quality of a musical note depends upon
(a) its frequency
(b) its amplitude
(c) the wave velocity
(d) its harmonic content
Ans: (d)
313. X-rays are used for the study of crystal structure because
(a) X-rays are completely absorbed by the crystal
(b) the wavelength of X-rays is of the same order of magnitude as the interatomic spacing in crystals
(c) the wavelength of X-rays is very small in comparison with the interatomic spacing in crystals
(d) the crystals are completely transparent to X-rays
Ans: (b)
314. A wave undergoes reflection from a rigid boundary. One of its characteristic parameters that changes is
(a) frequency (b) phase
(c) velocity (d) wavelength
Ans: (b)
315. Which of the following types of wave is used by computed tomography employed for visualisation of the internal structure of human body?
(a) X-rays (b) Sound waves
(c) Magnetic resonance
(d) Radioisotopes
Ans: (a)
316. An echo will be heard if the minimum distance between the source of sound and obstacle is
(a) 10 m (b) 1m (c) 15 m (d) 17 m
Ans: (d)
317. Assertion (A) Radio waves bend in a magnetic field.
Reason (R) Radio waves are electromagnetic in nature.
Codes
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true, but R is not the correct explanation of A
(c) A is true, but R is false
(d) A is false, but R is true
Ans: (d)
318. Consider the following statements
1. A flute of smaller length produces wavesof lower frequency.
2. Sound travels in rocks in the form of longitudinal elastic waves only.
Which of the statement(s) given above is/are correct?
(a) Only 1 (b) Only 2
(c) Both 1 and 2 (d) Neither 1 nor 2
Ans: (b)
319. The technique used to transmit audio signals in television broadcasts is
(a) amplitude modulation
(b) frequency modulation
(c) pulse code modulation
(d) time division multiplexing
Ans: (b)
320. The light wave is
(a) mechanical wave
(b) non-mechanical wave
(c) either mechanical or non-mechanical wave depends upon the medium through which it passes
(d) Only (a) and (c) is correct
Ans: (a)
321. Velocity of sound in air
1. decreases with temperature
2. increases with temperature
3. increases with pressure
4. is independent of pressure
Which of the above are true?
(a) 2 and 3 (b) 1, 2 and 3
(c) 2 and 4 (d) 1, 2, 3 and 4
Ans: (c)
322. When a stone is dropped on the surface of still water, the waves produced are
(a) longitudinal (b) transverse
(c) stationary
(d) partly transverse and partly longitudinal
Ans: (d)
323. A noise level of 100 decibel would correspond to
(a) sound from a noisy street
(b) just audible sound
(c) noise from a machine shop
(d) ordinary conversation
Ans: (c)
324. Which one of the following does TV remote control unit use to operate a TV set?
(a) Light waves (b) Sound waves
(c) Microwaves (d) Radiowaves
Ans: (d)
325. When light waves pass from air to glass the variables affected are
(a) wavelength, frequency and velocity
(b) velocity and frequency
(c) wavelength and frequency
(d) wavelength and velocity
Ans: (d)
326. When the frequency distribution is normal
(a) mean, mode and median are identical
(b) median, mode and mean are all different from one another
(c) mean is greater than mode
(d) mean is greater than median
Ans: (a)
327. Stationary waves are so called because in them
(a) same occurs no flow of energy
(b) the interference effect can’t be observed
(c) the particles of the medium are not disturbed at all
(d) the particles of the medium do not execute SHM
Ans: (a)
328. Sound waves do not exhibit the phenomenon of
(a) refraction (b) interference
(c) polarisation (d) diffraction
Ans: (c)
329. When a wave goes from one level to another, there is a change in the
1. frequency 2. velocity
3. amplitude 4. wavelength Choose the correct answer.
(a) 1, 2 and 3
(b) 2, 3 and 4
(c) 2 and 3
(d) 1, 2, 3 and 4
Ans: (b)
330. The Doppler’s effect is applicable for
(a) light wave
(b) space wave
(c) sound wave
(d) All of the above
Ans: (d)
331. The velocity of sound in air is affected by change in the
1. moisture content of air
2. temperature of air
3. composition of air
4. atmospheric pressure Choose the correct answer.
(a) 1, 2 and 3 (b) 2, 3 and 4
(c) 1, 2 and 4 (d) 1, 3 and 4
Ans: (b)
332. The velocity of sound is generally greater in solids than in gases because
(a) the density of solids is low and the elasticity is high
(b) the elasticity of solids is very high
(c) the density of solids is high and the elasticity is low
(d) Both the density and elasticity of solids are very low
Ans: (b)
333. When two sound waves are superimposed, beats are produced when they have
(a) different velocities
(b) different phases
(c) different frequencies
(d) different amplitudes and phases
Ans: (c)
334. Assertion (A) The velocity of sound in air increases due to the presence of moisture in it.
Reason (R) The presence of moisture in air lowers the density of air.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true, but R is not the correct explanation of A
(c) A is true, but R is false
(d) A is false, but R is true
Ans: (d)
335. The velocity of sound produced by a vibrating body varies
(a) inversely as the frequency of the medium
(b) inversely as the density of the medium
(c) directly as the square root of density of the medium
(d) directly as the square root of frequency of the medium
Ans: (b)
336. A source of sound waves towards an observer
(a) the wavelength of sound in the medium towards the observer is decreased
(b) the frequency of the source is increased
(c) the velocity of the sound in the medium is increased
(d) the amplitude of vibration of the particles is increased
Ans: (b)
337. In case of moving source of sound approaching the observer
(a) wavelength of sound appears to be more
(b) wavelength of sound appears to be less
(c) the frequency appears to be less
(d) None of the above
Ans: (b)
338. X-rays are heavily absorbed by lead atoms, but to obtain X-rays photograph of stomach barium sulphate is usually given to the patient instead of lead salt, because
(a) lead salts given fainter image
(b) lead salts are more poisonous
(c) barium salts reflect less
(d) barium salts give brighter image
Ans: (b)
339. Structure of solids is investigated by using
(a) -rays (b) X-rays
(c) cosmic rays
(d) infraredradiation
Ans: (b)
340. X-rays absorption will be maximum for the sheets of
(a) copper (b) iron
(c) silver (d) lead
Ans: (d)
341. Learned Indian classical vocalists do not like the accompaniment of a harmonium because
(a) notes of the harmoniumare too shrill
(b) tempered scale is used in the harmonium
(c) diatomic scale is used in the harmonium
(d) intensity of the notes of the harmonium is too large
Ans: (b)
342. The waves used for a communication through artificial satellite are
(a) radio waves in the FM band
(b) radio waves in the AM band
(c) microwaves
(d) None of the above
Ans: (c)
343. Consider the following statements
1. In sound waves, the vibrations are perpendicular to the direction in which the wave travels.
2. Sound waves are elastic waves.
Which of the statement(s) given above is/are correct?
(a) Only 2 (b) Only 1
(c) Both 1 and 2 (d) Neither 1 nor 2
Ans: (a)
344. Velocity of electromagnetic waves in a medium depends upon
(a) mechanical and electrical properties of medium
(b) electrical and magnetic properties of medium
(c) thermal propertics of medium
(d) None of the above
Ans: (b)
345. When a source of sound is in motion towards a stationary observer, the effect observed is
(a) decrease in the velocity of sound only
(b) increase in the frequency of sound only
(c) increase in the velocity of sound only
(d) increase in both the velocity and the frequency of sound
Ans: (a)
346. When an aeroplane attains a speed higher than the speed of sound in air a loud bang is heard, this is because
(a) its wings vibrate so violently that the bang is heard
(b) it explodes
(c) it produces a shock wave which is received as the bang
(d) the normal engine noises undergo a doppler shift to generate the bang
Ans: (b)
347. Red shifts is an illustration of
(a) high frequency absorption
(b) low temperature emission
(c) doppler effect
(d) unknown phenomenon
Ans: (a)
348. Speed of sound in a gas is proportional to
(a) square root of adiabatic elasticity
(b) isothermal elasticity
(c) square root of isothermal elasticity
(d) adiabatic elasticity
Ans: (c)
349. Sound waves in air are …. waves.
(a) radio (b) transverse
(c) longitudinal (d) electromagnetic
Ans: (b)
350. Ultrasonic waves are used for stirring liquid solutions because they
(a) can produce perfectly homogenous solutions
(b) do not produce chemical reactions in the solution
(c) are easy to produce
(d) do not produce noise during the operation
Ans: (c)
351. The waves moving from a sitar to a listener in air are
(a) transverse stationary
(b) transverse progressive
(c) longitudinal progressive
(d) longitudinal stationary
Ans: (b)
352. Sound waves of wavelength greater than that of audible sound are called
(a) ultrasonic waves
(b) infrasonic waves
(c) sonic waves (d) seismic waves
Ans: (c)
353. The length of a second pendulum (g /980 /) 2 cm s is nearly
(a) 25 cm (b) 50 cm
(c) 100 cm (d) 300 cm
Ans: (a)
354. Assertion (A) The energy (E) and momentum (p) of a photon are related by p=E/c.
Reason (R) The photon behaves like a particle.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true, but R is not the correct explanation of A
(c) A is true, but R is false
(d) A is false, but R is true
Ans: (c)
355. Velocity of wave in a string (thread) is
(a) directly porportional to its mass per unit length
(b) inversely proportional to the mass per unit length
(c) proportional to square root of mass per unit length
(d) None of the above
Ans: (d)
356. A progressive wave or travelling wave
(a) is that travelling in the + x-direction
(b) is that travelling in either (+)ve x-direction or (–) ve x-direction
(c) p is that travelling perpendicular to the x-axis
(d) None of the above
Ans: (d)
357. In an electromagnetic wave,
1. electric field and magnetic field are parallel to each other.
2. electric field and magnetic field are perpendicular to each other.
3. electric field and magnetic field both are perpendicular to direction to propagation of wave.
(a) 1 and 2 (b) All are correct
(c) Only 2 (d) 2 and 3
Ans: (c)
358. Which is the correct order of wave lengths of wave Given, R––shows the wavelength for radiowave. M––shows the wavelength for microwave V—shows the wavelength for visible light U—shows the wavelength for ultraviolet light
(a) R < M < V < U
(b) M > R > V > U
(c) R > M > U > V
(d) R > M > V > U
Ans: (c)
359. A person rings a metallic bell near a strong concrete wall. He hears the echo after 0.3 s. If the sound moves with a speed of 340 m/s, how far is the wall from him?
(a) 102 m
(b) 11 m
(c) 51 m
(d) 30 m
Ans: (c)
360. Two men are standing at a distance of 100 m. In the middle of the distance between them the 10 m gap is vacuum, one calls another (second)
(a) second men will listen some later
(b) second men will listen some shorter
(c) second men will listen never
(d) It cannot be determined
Ans: (c)
361. Which one of the following statements is not correct?
(a) Sound waves in gases are longitudinal in nature
(b) Sound waves having frequency below 20 Hz are known as ultrasonic waves
(c) Sound waves having higher amplitudes are louder
(d) Sound waves with high audible frequencies are sharp
Ans: (b)
362. Which one of the following statements is correct? The velocity of sound
(a) does not depend upon the nature of media
(b) is maximum in gases and minimum in liquids
(c) is maximum in solids and minimum in liquids
(d) is maximum in solids and minimum in gases
Ans: (d)
363. A sound wave has frequency of 2 kHz and wavelength of 35 cm. If an observer is 1.4 km away from the source, after what time interval could the observer hear the sound?
(a) 2 s
(b) 20 s
(c) 0.5 s
(d) 4 s
Ans: (a)
364. The loudness of sound is related to
(a) its frequency
(b) its amplitude
(c) its speed
(d) its pitch
Ans: (b)
Part 13. Heat
365. The energy that can harness heat stored below the earth’s surface is known as
(a) thermal energy
(b) tidal energy
(c) nuclear energy
(d) geothermal energy
Ans: (d)
366. The temperature of boiling water in steam engine may be high because
(a) there are dissolved substances in water
(b) there is low pressure inside the boiler
(c) there is high pressure inside the boiler
(d) the fire is at very high temperature
Ans: (c)
367. At upper atmosphere, an astronaut feels
(a) extremely hot (b) slightly hotter
(c) extremely cool (d) slightly cooler
Ans: (c)
368. The wavelength of the radiation emitted by a body depends upon
(a) the temperature of the surface
(b) the area of the surface
(c) the nature of the surface
(d) All of the above factors
Ans: (a)
369. Which of the following is the best conductor of the heat?
(a) Mercury (b) Silver
(c) Leather (d) Benzene
Ans: (b)
370. The celsius temperature is a/an
(a) relative temperature
(b) absolute temperature
(c) specific temperature
(d) approximate temperature
Ans: (c)
371. The cloud float in the atmosphere because of their low
(a) velocity (b) temperature
(c) density (d) pressure
Ans: (c)
372. What is the principle by which a cooling system (Radiator) in a motor car works?
(a) Convection (b) Conduction only
(c) Radiation only
(d) Both conduction and radiation
Ans: (a)
373. The change of a solid into vapour directly is called
(a) vaporization (b) freezing
(c) melting (d) sublimation
Ans: (d)
374. White clothes are cooler than black ones because they
(a) absorb all the light that reaches them
(b) reflect all the light that reaches them
(c) will not allow the light to penetrate
(d) cool the sun light completely
Ans: (b)
375. Low temperatures (cryogenics) find application in
(a) space travel, surgery and magnetic leviation
(b) surgery, magnetic leviation and telemetry
(c) space travel, surgery and telemetry
(d) space travel, magnetic leviation and telemetry
Ans: (a)
376. When water is heated from 0°C to 10°C, its volume
(a) increases
(b) decreases
(c) does not change
(d) first decreases and then increases
Ans: (d)
377. Which of the following is the example of ideal black body?
(a) Black board (b) Kajal
(c) A pin hole box
(d) None of these
Ans: (c)
378. Metal tea pots have wooden handles because
(a) wood is a bad conductor of heat
(b) it prevents electric shock
(c) it gives beauty to the pots
(d) it is hygienic
Ans: (a)
379. Transfer of heat energy from a heater coil to the cooking vessel takes place through the process of
(a) convection only
(b) conduction and convection only
(c) radiation and convection only
(d) convection, conduction and radiation
Ans: (c)
380. The temperature of water at the bottom of a waterfall is higher than that at the top because
(a) water at the bottom has greater potential energy
(b) the surface at the bottom provides heat
(c) kinetic energy of falling water is converted into heat
(d) falling water absorbs heat from the surroundings
Ans: (c)
381. At normal temperature due to the puncture, the compressed air inside the tube of a car wheel suddenly starts coming out. Then the air inside the tube
(a) starts becoming hotter
(b) starts becoming cooler
(c) remains at the same temperature
(d) may become hotter or cooler depending on the amount of water vapour present in the air
Ans: (b)
382. Which one of the following statements is not correct?
(a) The Kelvin scale of temperature is called the Absolute scale
(b) Visible light radiation has wavelength range of 400-700 nm
(c) The capacity to do work is called power
(d) The wavelength of Gamma rays is less than that of X-rays
Ans: (c)
383. Water is used in hot water bags because
(a) it is easily obtained
(b) it is cheaper and is not harmful
(c) it has high specific heat
(d) it is easy to heat water
Ans: (c)
384. How can boiling point of a liquid be reduced?
(a) By adding a solid of lowermelting point
(b) By dissolving a soluble solid in it
(c) By increasing the pressure on the liquid
(d) By decreasing the pressure on the liquid
Ans: (d)
385. Two bodies A and B are of same mass and same amount of heat is given to both of them. If the temperature of A increases more than that of B because of heat addition, then
(a) the specific heat capacity of A is more than that of B
(b) the specific heat capacity of A is less than that of B
(c) both A and B have the same specific heat capacity but A has greater thermal conductivity
(d) both A and B the same specific heat capacity but B has greater thermal conductivity
Ans: (b)
386. Which one of the following is true for the flow of water from high level to low (at constant temperature and pressure)?
(a) G =0 (b) G =1
(c) G <0 (d) G =–1
Ans: (c)
387. A gas thermometer is more sensitive than a liquid thermometer because a gas
(a) is lighter than liquid
(b) expands more than a liquid
(c) is easy to obtain
(d) does not change state easily
Ans: (b)
388. Night are cooler in the deserts than in the plains because
(a) sand radiates heat more quickly than the earth
(b) the sky remain clear most of the time
(c) sand absorbs heat quickly than the earth
(d) None of the above
Ans: (a)
389. A real gas can be liquified by the application of pressure when its temperature is
(a) above the room temperature
(b) above the inversion temperature
(c) at the Boyle temperature
(d) at the critical temperature
Ans: (d)
390. After a hot sunny day, people sprinkle water on the roof-top because
(a) water helps air around the roof-top to absorb the heat instantly
(b) water has lower specific heat capacity
(c) water is easily available
(d) water has large latent heat of vaporisation
Ans: (d)
391. The best conductor of heat among the following is
(a) alcohol (b) mercury
(c) ether (d) water
Ans: (b)
392. Clothes keep us warm in winter because they
(a) supply heat
(b) do not radiate heat
(c) prevent air from contacting the body
(d) prevent the heat of the body from escaping
Ans: (d)
393. The water from a hand-pump is warm in winter because
(a) our body is cold in winter and water appears to be warm
(b) the temperature inside the earth is higher than the atmospheric temperature
(c) the pumping process causes friction which warms up the water
(d) inside water comes out and absorbs heat from the environment
Ans: (b)
394. Which one of the following statements is not correct?
(a) Conduction can occur easily in solids, less easily in liquids but hardly at all in gases
(b) Heat energy is carried by moving particles in a convection current
(c) Heat energy is carried by electromagnetic waves in radiation
(d) The temperature at which a solid changes into a liquid is called the boiling point
Ans: (d)
395. Consider the following statements
1. Steam at 100°C and boiling water at 100°C contain same amount of heat.
2. Latent heat of fusion of ice is equal to the latent heat of vaporisation of water.
3. Conditioner heat is extracted from the room air at the evaporator coils and is rejected out at the condenser coils.
Which of these statements is/are correct?
(a) 1 and 2 (b) 2 and 3
(c) only 2 (d) only 3
Ans: (d)
396. In the winter season if we touch two blocks one of iron and another of wood in the early morning then the block of iron appears to be more cold because
(a) the temperature of the iron block is less than that of the wooden block
(b) iron is a bad conductor of heat in comparison of the wood
(c) iron is a good conductor of heat in comparison of the wood
(d) the block of iron is heavier than the wooden block
Ans: (c)
397. The silvering in thermos flasks is done to avoid heat transfer by
(a) convection (b) conduction
(c) radiation (d) Both a and b
Ans: (c)
398. A hollow sphere of radius R, a hollow cube of side R and thin circular plate of radius R made up of the same material, are all heated to 20° C above room temperature. When left to cool in the room, which of them will reach the room temperature first?
(a) Circular plate (b) Cube
(c) Sphere
(d) All of them will reach the room temperature at the same time
Ans: (c)
399. At absolute zero temperature, the kinetic energy of the molecules
(a) becomes constant
(b) becomes maximum
(c) becomes minimum
(d) becomes zero
Ans: (c)
400. Heat is transmitted from higher to lower temperature through actual mass motion of the molecules in
(a) conduction (b) radiation
(c) convection (d) All of these
Ans: (c)
401. A glass container cracks when very hot tea is poured into it a probable reason for this is the
(a) low specific heat of gas
(b) low thermal conductivity of glass
(c) high thermal conductivity of glass
(d) None of the above
Ans: (b)
402. Woollen clothes keep the body warm because
(a) wool absorbs radiant heat from outer objects
(b) wool increases the temperature of the body
(c) wool is the bad conductor of the heat so it does not allow heat to flow out of the body
(d) wool rejects heat from outer objects
Ans: (c)
403. Water is usual as coolant in the radiator of a car engine because it
(a) has low boiling point
(b) has low density
(c) is easily available
(d) has high specific heat
Ans: (d)
404. Consider the following statements
1. Stefan’s constant is the same for all black bodies.
2. Thermal radiations travel with the speed of 3 -108 m/s.
3. Thermal radiation exhibit diffraction.
4. Stefan’s law is applicable for all heated bodies.
Which of the statements given above are correct?
(a) 1, 3 and 4 (b) 2, 3, and 4
(c) 1, 2 and 3 (d) 1, 2, 3 and 4
Ans: (c)
405. Consider the following statements
1. Thermal radiation are electromagnetic waves.
2. Thermal radiations are reflected from mirror.
3. All bodies emit thermal radiations at all temperatures.
4. Thermal radiations of all wavelengths travel in free space with same velocity.
Which of the statement(s) given above are correct?
(a) 1, 2 and 3 (b) 1, 3 and 4
(c) 1, 2, and 4 (d) 1, 2, 3, and 4
Ans: (d)
406. According to Newton’s law of cooling, the rate of cooling of a body is proportional to the
(a) temperature of the body
(b) temperature of the surrounding
(c) difference of the temperature of the body and its surrounding
(d) None of the above
Ans: (c)
407. Consider the following statements
1. Heat can be reflected by mirror.
2. Heat is a form of energy.
3. Heat cannot pass through vacuum.
4. Heat is an electromagnetic radiation.
Which of the statements given above are correct?
(a) 1, 2, and 3
(b) 1, 3 and 4
(c) 2 and 4
(d) 1, 2, 3 and 4
Ans: (c)
408. The temperature of a gas is measured with a
(a) gas thermometer
(b) platinum resistance thermometer
(c) vapour pressure thermometer
(d) pyrometer
Ans: (d)
409. The first law of thermodynamics is concerned with the conservation of
(a) energy
(b) number of molecules
(c) number of moles (d) temperature
Ans: (a)
410. Device used to measure very high temperature is
(a) bolometer (b) pyrometer
(c) thermometer (d) calorimeter
Ans: (b)
411. A large ice berg melts at the base but not at the top because
(a) ice at the top is different kind
(b) higher pressure at the base lowers the melting point of ice
(c) ice at the base contain impurities
(d) the base of iceberg remains in warmer conditions
Ans: (b)
412. Cooking longest time takes
(a) at Shimla (b) at Mt. Everest
(c) at the sea level (c) None of these
Ans: (b)
413. Ametal screw top on a glass bottle which appears to be stuck could be opened by using the fact that
(a) the metal expands more than the glass when both are heated
(b) the metal and glass expand identically when heated
(c) the metal shrinks when heated
(d) both metal and glass shrink when cooled
Ans: (b)
414. A piece of ice, 100 g in mass is kept at 0 °C. The amount of heat it requires to melt at 0 °C is (take latent heat of melting of ice to be 333.6 J/g)
(a) 750.6 J (b) 83.4 J
(c) 33360 J (d) 3.336 J
Ans: (c)
415. Assertion (A) Internal energy of an ideal gas does not depend upon volume of the gas.
Reason (R) This is because internal energy of ideal gas depends on temperature of gas.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true, but R is not the correct explanation of A
(c) A is true, but R is false
(d) A is false, but R is true
Ans: (b)
416. Assertion (A) At room temperature water does not sublimate from ice to steam.
Reason (R) The critical point of water is much above the room temperature.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true, but R is not the correct explanation of A
(c) A is true, but R is false
(d) A is false, but R is true
Ans: (a)
417. Assertion (A) Water kept in an open vessel will quickly evaporate on the surface of the moon.
Reason (R) The temperature at the surface of the moon is much higher than boiling point of water.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true, but R is not the correct explanation of A
(c) A is true, but R is false
(d) A is false, but R is true
Ans: (c)
418. Assertion (A) When two systems, which are in thermal equilibrium with a third system, then all system will be in thermal equilibrium with each other.
Reason (R) The heat flows spontaneously from a system at a higher temperature to a lower temperature in a system.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true, but R is not the correct explanation of A
(c) A is true, but R is false
(d) A is false, but R is true
Ans: (a)
419. Match the following lists
List I List II
A. In an isothermal process 1. Temperature remains constant
B. In an adiabatic process 2. Volume remains constant
C. In an isobaric process 3. Heat content remains constant
D. In an isochoric process 4. Pressure remains constant
Codes A B C D A B C D
(a) 1 2 3 4 (b) 1 3 4 2
(c) 4 3 2 1 (d) 3 2 1 4
Ans: (b)
420. In a pressure cooker, the cooking is faster because
(a) more steam is available to cook the food at 1000°C
(b) the boiling point of water is lowered by the increased pressure
(c) the boiling point of water is raised by the increased pressure inside the cooker
(d) None of the above
Ans: (c)
421. Which of the following is the correct device for the detection of thermal radiation?
(a) Liquid-in-glass thermometer
(b) Constant volume gas thermometer
(c) Thermophile
(d) None of the above
Ans: (c)
422. It is difficult to cook at high altitudes because
(a) of high moisture content here
(b) there is less oxygen in air
(c) due to decrease in atmospheric pressure, the boiling point of water decreases
(d) due to falling temperature, more heat has to be given
Ans: (c)
423. A cooking pot should have
(a) high specific heat and high conductivity
(b) high specific heat and low conductivity
(c) low specific heat and high conductivity
(d) low specific heat and low conductivity
Ans: (c)
424. A gas is enclosed in a container which is then placed on a fast moving train. The temperature of the gas
(a) falls
(b) rises
(c) remain unchanged
(d) becomes unsteady
Ans: (c)
425. Match the following lists
List I List II
A. Zeroth law of thermodynamics 1. Give us the concept of temperature
B. First law of thermodynamics 2. Defines internal energy
C. Second law of thermodynamics 3. Change in internal energy is zero
D. In a complete cycle of changes 4. The efficiency of on engine is always less than unity
Codes A B C D A B C D
(a) 1 2 3 4 (b) 1 2 4 3
(c) 4 3 2 1 (d) 3 2 4 1
Ans: (b)
426. The temperature at which the vapour pressure of a liquid becomes equal to the external (atmospheric) pressure is its
(a) inversion point
(b) melting point
(c) boiling point
(d) None of these
Ans: (c)
427. Heat capacity of substance is infinite. It means
(a) infinite heat is taken in
(b) infinite heat is given out
(c) no change in temperature whether heat is taken in or given out
(d) All of the above
Ans: (c)
428. The freezer in a refrigerator is located at the top section so that
(a) the motor is not heated
(b) the heat gained from the environment is high
(c) the heat gained from the environment is low
(d) the entire chamber of the refrigerator is cooled quickly due to convection
Ans: (d)
429. A closed bottle containing water at room temperature is taken to the moon and thenthelidisopened.Thewaterwill
(a) boil (b) freeze
(c) decompose into hydrogen and oxygen
(d) not change at all
Ans: (b)
430. A refrigerator, with its power on, is kept in closed room with its door open. The temperature of the room will
(a) fall
(b) rise
(c) remains the same
(d) None of the above
Ans: (b)
431. A metallic plate sticks firmly on the mouth of a water vessel made from another metal. By way of heating, one can detach the plate from the vessel. This is because heat expands
(a) the vessel
(b) both the vessel and the plate equally
(c) the vessel more than the plate
(d) the vessel and contracts the plate
Ans: (c)
432. Water density is maximum at the temperature of
(a) 4°C (b) 4°C
(c) 4 K (d) None of these
Ans: (a)
433. The product of the pressure and volume of an ideal gas is
(a) directly proportional to its temperature
(b) inversely proportional to its temperature
(c) a constant
(d) approximately equal to the universal gas constant
Ans: (a)
434. The relation between volume and temperature of a sample of water in the range 0°C to 100°C is best represented by
Ans: (c)
435. Pressure exerted by gas is
(a) inversely proportional to the density of the gas
(b) independent of the density of the gas
(c) directly proportional to the square of the density of the gas
(d) directly proportional to the density of the gas
Ans: (d)
436. A gas behaves as an ideal gas more closely at
(a) low pressure and high temperature
(b) high pressure and high temperature
(c) low pressure and low temperature
(d) high pressure and low temperature
Ans: (c)
437. The specific heat of a gas at constant pressure is greater than the specific heat at constant volume because
(a) work is done in the expansion of the gas at constant volume
(b) work is done in the expansion of the gas at constant pressure
(c) the molecular collision increase at constant pressure
(d) the attraction between the molecules increases at constant pressure
Ans: (b)
438. The pressure exerted on the walls of the container by a gas is due to the fact that the gas molecules
(a) stick to the walls
(b) lose their kinetic energy
(c) change their momenta due to collision with the walls
(d) are accelerated towards the walls
Ans: (c)
439. Which one of the following substances has greatest specific heat?
(a) Water (b) Mercury
(c) Iron (d) Copper
Ans: (a)
440. When a temperature is gradually decreased, the specific heat of substance is
(a) increased
(b) decreased
(c) remain unchanged
(d) None of the above
Ans: (c)
441. The graph which represent the variation of mean kinetic energy of molecules with temperature °C is
Ans: (c)
442. Consider the following statements
1. Glaciers always melt at the bottom first.
2. Calorimeters are generally made of coppers.
3. The unit of latent heat is cal/g.
4. If a substance contracts on heating, its co-efficient of linear expansion is negative.
Which of the statements given above are correct?
(a) 1, 2 and 3 (b) 2, 3 and 4
(c) 1, 2 and 4 (d) 1, 2, 3 and 4 Volume Temp Volume Temp Volume Temp Volume Temp
(a) (b)
(c) (d)
Ans: (d)
443. The latent heat of vaporisation of a substance is always
(a) greater than its latent heat of fusion
(b) greater than its latent heat of sublimation
(c) equal to its latent heat of sublimation
(d) less than its latent heat of fusion
Ans: (a)
444. Consider the following statements
1. A heat engine is a device which converts heat energy into mechanical energy.
2. A heat engine essentially consists of source of heat at higher temperature, working substance and sink of heat at lower temperature.
3. In a diesel engine, a mixture of fuel vapours and air acts as the working substance.
4. Efficiency of a petrol engine is greater than diesel engine.
Which of the statements given above are correct?
(a) 1 and 2 (b) 1 and 3
(c) 1, 2 and 3 (d) All of these
Ans: (c)
445. Dry ice is
(a) ice cube (b) sodium chloride
(c) liquid nitrogen
(d) solid carbon dioxide
Ans: (d)
446. A liquids boils when its vapour pressure equals
(a) the atmosphere pressure
(b) the pressure of 76.0 cm column of mercury
(c) the critical pressure
(d) the dew point of the surroundings
Ans: (a)
447. Density of water is
(a) maximum at 0°C
(b) minimum at 0°C
(c) maximum at 4°C
(d) minimum at –4°C
Ans: (c)
448. When we rub our palms they gets heated but to a maximum temperature because
(a) heat is absorbed by our palm
(b) heat is lost in the environment
(c) produced of heat is stopped
(d) None of the above
Ans: (b)
449. Mud houses are cooler in summer and warmer in winter because
(a) Mud is superconductor of heat
(b) Mud is good conductor of heat
(c) Mud is bad conductor of heat
(d) None of the above
Ans: (c)
450. The brightness of a star depends on its
(a) size and temperature
(b) size and distance from the Earth
(c) size, temperature and mass
(d) size, temperature and distance from the Earth
Ans: (a)
451. When red glass is heated in dark room it will seem?
(a) Green (b) Purple
(c) Black (d) Yellow
Ans: (a)
452. Which one of the following statements with regard to expansion of materials due to heating is not correct?
(a) As ice melts, it expands uniformly up to 4°C.
(b) Mercury thermometer works using the principle of expansion due to heating.
(c) Small gap is kept between two rails to allow for expansion due to heating.
(d) The length of metallic wire increases when its temperature is increased.
Ans: (a)
453. Which of the following p-V graphs best represents on adiabatic process?
Ans: (d)
454. Which of the following p-V graphs best represents an isothermal process?
Ans: (c)
455. The field created by heat (z-e heat field) is a
(a) vector field
(b) scalar field
(c) neither vector nor scalar
(d) sometime vector and sometime scalar field
Ans: (b)
456. Which among the following represents cooling curve?
Ans: (d)
Part 14. Optics
457. Which one among the following has the highest energy?
(a) Blue light (b) Green light
(c) Red light
(d) Yellow light
Ans: (a)
458. Which one of the following reflects back more sunlight as compared to other three?
(a) Sand desert
(b) Paddy crop lan
(c) Land covered with fresh snow
(d) Prairie land
Ans: (c)
459. A laser beam is always
(a) a convergent beam
(b) a divergent beam
(c) a parallel beam
(d) divergent to start with and parallel later on
Ans: (c)
460. The head mirror used by ENT doctors is
(a) concave (b) convex
(c) plane (d) planoconvex
Ans: (a)
461. The image formed on the retina of a human eye is
(a) virtual and inverted
(b) virtual and erect
(c) real and erect
(d) real and inverted
Ans: (d)
462. An object is placed at the focus of a concave mirror. The image will be
(a) real, inverted, same size at the focus
(b) real, upright, same size at the focus
(c) virtual, inverted, highly enlarged at infinity
(d) real, inverted, highly enlarged at infinity
Ans: (d)
463. A lady is standing in front of a plane mirror at a distance of 1 m from it. She walks 60 cm towards the mirror. The distance of her image now from herself (ignoring the thickness of the mirror) is
(a) 40 cm (b) 60 cm
(c) 80 cm (d) 120 cm
Ans: (a)
464. A lens, immersed in a liquid becomes invisible when
(a) the focal length of the lens is zero
(b) the focal length of the lens is infinite
(c) the refractive index of the lens is less than the refractive index of the liquid
(d) the refractive index of the lens is equal to the refractive
Ans: (d)
465. Different objects at different distances are seen by the eye. The parameter that remains constant is
(a) the focal length of the eye lens
(b) the object distance fromthe eye lens
(c) the radii of curvature of the eye lens
(d) the image distance fromthe eye lens
Ans: (d)
466. An object is kept 5 cm in front of a concave mirror of focal length 15 cm. What will be the nature of the image?
(a) virtual, not magnified
(b) virtual, magnified
(c) real, not magnified
(d) real, magnified
Ans: (b)
467. Cylindrical lens is used by a person suffering from
(a) astigmatism (b) myopia
(c) hypermetropia (d) presbyopia
Ans: (a)
468. How far must a girl stand in front of a concave spherical mirror of radius 120 cm to see an erect image of her face, four times its natural size?
(a) 40 cm from the mirror
(b) 45 cm from the mirror
(c) 50 cm from the mirror
(d) 55 cm from the mirror
Ans: (b)
469. Consider the following statements
1. Light waves can travel in vacuum
2. Light waves can be refracted
3. Light waves are electromagnetic
Which of the statements given above are correct?
(a) 1,2 and 3 (b) 2 and 3
(c) 1 and 3 (d) 1 and 2
Ans: (a)
470. The power of lens is – 2 D. What is its focal length?
(a) 2 m (b) 1.5 m
(c) 1.0 m (d) 0.5 m
Ans: (d)
471. Diffusion of light in the atmosphere takes place due to
(a) carbon dioxide (b) dust particles
(c) helium (d) water vapours
Ans: (b)
472. Consider the following natural phenomena
1. Terrestrial heating 2. Reflection of light
3. Refraction of light 4. Diffraction of light Due to which of these phenomena is mirage formed?
(a) 1 and 2 (b) 2, 3 and 4
(c) 1 and 3 (d) Only 4
Ans: (c)
473. Which of the following types of light are strongly absorbed by plants?
(a) Violet and orange
(b) Blue and red
(c) Indigo and yellow
(d) Yellow and violet
Ans: (b)
474. To which one of the following process is the term CMYK related?
(a) railway signaling
(b) navigation (c) offset printing
(d) electronic voting machine
Ans: (c)
475. Which one of the following types of waves are used in a night vision apparatus?
(a) Radiowaves (b) Microwaves
(c) Infrared waves (d) None of these
Ans: (c)
476. A pencil is placed upright at a distance 10 cm from a convex lens of focal length 15 cm. The nature of the image of the pencil will be
(a) real, inverted and magnified
(b) real, erect and magnified
(c) virtual, erect and reduced
(d) virtual, erect and magnified
Ans: (c)
477. Consider the following statements
1. If magenta and yellow coloured circles intersect, the intersected area will have red colour.
2. If cyan and magenta coloured circles intersect, the intersected area will have blue colour.
Which of the statement(s) given above is/are correct?
(a) Only 1
(b) Only 2
(c) Both 1 and 2
(d) Neither 1 nor 2
Ans: (c)
478. Which one of the following phenomena cannot be attributed to the refraction of light?
(a) Twinkling of stars (b) Mirage
(c) Rainbow (d) Redshift
Ans: (d)
479. An object is placed at the centre of curvature of a concave mirror of focal length 16 cm. If the object is shifted by 8 cm towards the focus, the nature of the image would be
(a) real and magnified
(b) virtual and magnified
(c) real and reduced
(d) virtual and reduced
Ans: (d)
480. A double convex glass lens of focal length f and having a circular aperture is cut into two halves, each having a semicircular aperture. The focal length of each half is
(a) f (b) 2 f
(c) f/2 (d) infinity
Ans: (a)
481. Whose experiments proved that the speed of light was always the same?
(a) James Clark Maxwell
(b) Michelson and Morley
(c) Miller and Stanley
(d) Werner Heisenberg
Ans: (b)
482. Why is red light employed for danger signals?
(a) Red colour is smothing to the eye
(b) Human eye is most sensitive to red colour
(c) Red light is scattered least
(d) Red light is scattered most
Ans: (c)
483. The phenomenon of formation of three dimensional image by entrance of two light beams from laser or other coherent sources of light is called
(a) optical photography
(b) X-rays photography
(c) radiography
(d) holography
Ans: (d)
484. The energy associated with the light depends upon
(a) its speed
(b) medium through which it passes
(c) its frequency
(d) All of thesce
Ans: (c)
485. The image formed by plane mirror is
(a) real (b) virtual
(c) may be virtual or real depending on the position of the object
(d) None of the above
Ans: (b)
486. Assertion (A) In the visible spectrum of light, red light is more energetic than green light.
Reason (R) The wavelength of red light is more than that of green light.
(a) A and R are individually true and R is the correct explanation of A
(b) A and R are individually true but R is not the correct explanation of A
(c) A is true, but R is false
(d) A is false, but R is true
Ans: (d)
487. A convex lens is used to form a real image of an object shown in the figure above. The object is coated with four different colours, violet (V), Indigo (I), Blue (B) and Green (G). Which of the following represents the image of the
Ans: (d)
488. An explosion takes place on the surface of moon. An astronaut at some distance from the site of explosion will
(a) observe light and hear sound caused by the explosion
(b) observe light but not hear sound caused by the explosion
(c) hear sound but not observe light caused by the explosion
(d) neither hear sound nor observe light caused by the explosion
Ans: (b)
489. A light wave travelling in a transparent homogeneous medium enters another transparent homogeneous medium of higher refractive index. The speed of light in the second medium
(a) is less than that in the first medium
(b) is more than that in the firstmedium
(c) is the same as that in the first medium
(d) may be more or less than that in the first medium depending on the angle of incidence
Ans: (a)
490. Least distance for clear vision to the normal eye is
(a) 25 cm (b) 25 mm
(c) 1/25 m (d) 20 cm
Ans: (a)
491. Consider the following statements
1. Compound microscope has objective lens with a very short focal length.
2. Simple microscope consists of a strong converging lens system.
3. Television camera converts the optical images into electrical video signals.
4. Hypermetropia is corrected by using a diverging lens.
Which of these statement(s) is/are correct?
(a) Only 4 (b) 2 and 3
(c) 1, 2 and 3
(d) 1, 2, 3 and 4
Ans: (c)
492. A myopic person has a power of –1.25 Dioptre. What is the focal length and nature of his lens?
(a) 50 cm and convex lens
(b) 80 cm and convex lens
(c) 50 cm and concave lens
(d) 80 cm and concave lens
Ans: (d)
493. To an observer on the lunar surface, during the day time the sky will appear to be
(a) light yellow (b) orange
(c) blue (d) black
Ans: (d)
494. In the phenomenon of dispersion of light, the light wave of shortest wavelength is
(a) accelerated and refracted the most
(b) slowed down and refracted themost
(c) accelerated and refracted the least
(d) slowed down and refracted the least
Ans: (c)
495. Which one of the following statements is correct?
(a) The image formed by a concave mirror for an object lying at infinity is at the principal focus, highly diminished, real and inverted.
(b) A ray of light parallel to the principal axis after reflection from a concave mirror appears to diverge from the principal focus of the mirror.
(c) The focal length of a spherical mirror is double of its radius of curvature.
(d) A ray of light travelling from rarer medium to a denser medium bends away from the normal.
Ans: (a)
496. If the angle between two plane mirrors is 60; then the number of image formed will be
(a) infinite (b) 7
(c) 6 (d) 5
Ans: (d)
497. The position, relative size and nature of the image formed by a concave lens for an object placed at infinity are respectively
(a) at focus, diminished and virtual
(b) at focus, diminished and real
(c) between focus and optical centre, diminished and virtual
(d) between focus and optical centre, magnified and real
Ans: (a)
498. Panchromatic photographic film is sensitive to
(a) light of red colour
(b) light of yellow colour
(c) light of violet colour
(d) the entire region of the visible spectrum
Ans: (d)
499. Two plane mirrors are inclined at an angle to one another. A ray of light incident on the first mirror and parallel to the second mirror is reflected from the second mirror parallel to the first mirror. What is the value of ?
(a) 0° (b) 45°
(c) 60°(d) 90°
Ans: (c)
500. Why does a tower appear larger and larger to a person approaching it?
1. The angle subtended by the tower at the eye, increases.
2. The focal length of eye lens increases.
3. The size of the image of the retina of eye increases. Select the correct answer using the codes given above.
(a) Only 1 (b) Only 3
(c) 1 and 3 (d) 1, 2 and 3
Ans: (c)
501. The primary colours in photography are
(a) red, blue, yellow
(b) red, yellow, green
(c) red, blue, green
(d) red, green, cyan
Ans: (c)
502. A water tank appears shallower when it is viewed from top due to
(a) rectilinear propagation of light
(b) reflection
(c) total internal reflection
(d) refraction
Ans: (d)
503. Lambert’s law is related to
(a) reflection (b) refraction
(c) interference (d) illumination
Ans: (d)
504. In summer, the mirages are seen due to the phenomenon of
(a) reflection of light
(b) total internal reflection
(c) interference of light
(d) diffraction of light
Ans: (b)
505. Consider the following statements
1. The focal length of the objective of a microscope is less than the focal length of the eyepiece.
2. The minimum distance between an object and its real image formed by a convex lens of focal length f is equal to it.
Which of the statement(s) given above is / are correct?
(a) Only 1
(b) Only 2
(c) Both 1 and 2
(d) Neither 1 nor 2
Ans: (c)
506. A complete circular rainbow may be seen from
(a) an elevated position
(b) an depressed position
(c) height cannot be affect
(d) ground surface
Ans: (a)
507. Electron microscope was invented by
(a) Knoll and Ernst Ruska
(b) Robert Koch
(c) Leeuwenhoek
(d) CPS Wanson
Ans: (a)
508. Which one of the following is used to remove astigmatism for a human eye?
(a) Concave lens (b) Convex lens
(c) Cylindrical lens (d) Prismatic lens
Ans: (c)
509. An optician prescribes a power /–0.5 diopter. The corresponding lens must be a
(a) convex lens of focal length 2 m
(b) convex lens of focal length 50 cm
(c) concave lens of focal length 2 m
(d) concave lens of focal length 50 cm
Ans: (c)
510. In which part of the eye lies the pigment, that decides the colour of the eyes of a person?
(a) Cornea (b) Choroid
(c) Iris (d) Vitreous body
Ans: (b)
511. Suppose a rocket ship is receding from the earth at a speed of 1 10 th the velocity of light. A light in the rocket ship appears blue to the passengers on the ship.What colour would it appear to an observer on the earth?
(a) Blue (b) Orange
(c) Yellow (d) Yellow-orange
Ans: (a)
512. Optical fibre works on the principle of
(a) total internal reflection
(b) refraction
(c) scattering
(d) interference
Ans: (a)
513. What is the essential difference between a terrestrial telescope and an astronomical telescope?
(a) One of the lenses in a terrestrial telescope is concave
(b) The final image formed in a terrestrial telescope is virtual
(c) A terrestrial telescope forms an erect image while an astronomical telescope forms an inverted image
(d) A terrestrial telescope forms an inverted image while an astronomical telescope forms an erect image
Ans: (c)
514. What is viewed through an electron microscope?
(a) Electrons and other elementary particles
(b) Structure of bacteria and viruses
(c) Inside of human stomach
(d) inside of the human eye
Ans: (b)
515. When a mirror is rotated by an angle, the reflected ray will rotated by
(a) 0°(b) 2
(c) (d) 2
Ans: (d)
516. An air bubble in water will act like a
(a) convex mirror (b) convex lens
(c) concave mirror (d) concave lens
Ans: (d)
517. Consider the following statements
1. Polaroids are used in the laboratory to produce and analyze a plane polarized light.
2. Red signal appears to be visible of a larger distances without any appreciable loss due to scattering.
3. Due to the scattering of light sky appears blue.
Which of the statement(s) given above is/are correct?
(a) 1 and 2 (b) Only 3
(c) 1, 2 and 3 (d) None of these
Ans: (c)
518. Total internal reflection can take place when light travels from
(a) diamond to glass
(b) water to glass
(c) air to water
(d) air to glass
Ans: (c)
519. When a CD (compact disc used in audio and video system) is seen in sunlight. Rainbow like colours are seen. This can be explained on the basis of the phenomenon of
(a) reflection and diffraction
(b) reflection and transmission
(c) diffraction and transmission
(d) refraction, diffraction and transmission
Ans: (d)
520. Which one of the following statements is not correct?
(a) The radius of curvature of a concave mirror is twice its focal length.
(b) Power of a convex lens is negative and that of a concave lens is positive.
(c) The radius of curvature of a plane mirror is infinity.
(d) When a ray of light passes from an optically denser medium to an optically rarer medium, the angle of refraction is greater than the corresponding angle of incidence.
Ans: (b)
521. The outside rearview mirror of modern automobiles is marked with warning “objects in mirror are closer than they appear”. Such mirrors are
(a) plane mirrors
(b) concave mirrors with very large focal lengths
(c) concave mirrors with very small focal lengths
(d) convex mirrors
Ans: (d)
522. According to the modern theory for nature of light, the light has
(a) particle nature only
(b) wave nature only
(c) both wave and particle (dual nature)
(d) Neither particle nature nor wave nature
Ans: (c)
523. Match the following lists
List I List II
A. Reflection 1.= sini/sinr
B. Refraction 2. Used for reducing glare
C. Interference 3. Light added to light produces darkness
D. Polarisation 4. Change in path of light without change in medium
Codes A B C D A B C D
(a) 1 2 3 4 (b) 4 3 1 2
(c) 4 1 3 2 (d) 3 1 4 2
Ans: (c)
524. The focal length of the lens of a normal human eye is about
(a) 25 cm (b) 1m
(c) 2.5 min (d)2.5 cm
Ans: (d)
525. The human eye has a lens which has a
(a) hard surface
(b) varying refractive index
(c) constant refractive index
(d) soft portion at its centre
Ans: (c)
526. Rainbow is formed due to a combination of
(a) dispersion and focussing
(b) refraction and absorption
(c) refraction and scattering
(d) dispersion and total internal reflection
Ans: (d)
527. When a ray of light is refracted by a prism such that the angle of deviation is minimum, then
(a) the angle of emergence is greater than angle of incidence
(b) the angle of emergence is equal to the angle of incidence
(c) the angle of emergence is smaller than the angle of incidence
(d) the sum of the angle of incidence and the angle of emergence is equal to 90°.
Ans: (b)
528. While looking at an image formed by a convex lens (one half of the lens is covered with a black paper), which one of the following will happen to the image?
(a) Half of the image will be visible.
(b) Intensity of the image will be diminished.
(c) Image will be inverted now.
(d) One can see an image of smaller size.
Ans: (b)
529. Myopia is due to
(a) older age
(b) shortening of eye ball
(c) elongation of eye ball
(d) irregular changes in the focal length of the eye lens
Ans: (c)
530. The spread in colours in a rainbow on sky is primarily due to
(a) dispersion of Sunlight
(b) reflection of Sunlight
(c) refraction of Sunlight
(d) total internal reflection of Sunlight
Ans: (b)
531. Total internal reflection of light is possible when light enters from
(a) vacuum to air (b) air to glass
(c) water to air (d) air to water
Ans: (c)
532. Consider the following statements about laws of refraction
1. The incident ray, the refracted ray and normal to the interface at the point of incidence, all lie in the same plane.
2. Whenever light goes from one medium to another, the frequency of light and phase of light do not change. However, the velocity of light and the wavelength of light change.
Which of the above statement(s) is/are correct?
(a) Only 2 (b) Only 1
(c) Both 1 and 2 (d) Neither 1 nor 2
Ans: (c)
533. Which of the following is not due to total internal reflection?
(a) Mirage on hot summer days
(b) Brilliance of diamond
(c) Difference between apparent and real depth of a pond
(d) Working of optical fibre
Ans: (c)
534. Consider the following statements
1. The minimum size of a mirror required to see the full image of a person is half the height of the person.
2. A convex mirror always forms a virtual, erect and diminished image.
3. The laws of reflection are true for all reflecting surfaces.
4. The focal length of a plane mirror is zero.
Which of the statement(s) given above is/are correct?
(a) 1, 2 and 3 (b) 1, 3 and 4
(c) 2, 3 and 4 (d) 1, 2, 3 and 4
Ans: (a)
535. Total internal reflection can occur when light tends to pass from
(a) a rarer to a denser medium
(b) a denser to a rarer medium
(c) one medium to another of equal refractive index
(d) None of the above
Ans: (b)
536. Match the following lists
List I List II
A. Interference of light 1. Coherent sources
B. Doppler’s effect 2. Change in frequency
C. Diffraction of light 3. Different colours of light are due to different size corpulse
D. Corpuscular theory of light 4. Bending of light around the corner
Codes A B C D A B C D
(a) 1 2 3 4 (b) 1 2 4 3
(c) 4 3 2 1 (d) 2 1 3 4
Ans: (b)
537. Assertion (A) Light shows the phenomena of interference, diffraction and polarization.
Reason (R) Because light behaves as corpuscles.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true but R is not a correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
Ans: (b)
538. When viewed in white light, soap bubbles show colours because of
(a) scattering (b) diffraction
(c) interference (d) dispersion
Ans: (c)
539. Assertion (A) The sun looks bigger in size at sunrise and sunset than during day.
Reason (R) The phenomenon of diffraction bends light rays.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true but R is not a correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
Ans: (b)
540. Assertion (A) Colours can be seen in thin layers of oil on the surface of water.
Reason (R) White light is composed of seven colours.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true but R is not a correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
Ans: (b)
541. To an observer on the earth the stars appear to twinkle. This can be described to
(a) frequent absorption of star light by earth’s atmosphere
(b) the fact that stars do not emit light continuously to their own atmosphere
(c) the refractive index fluctuations in earth’s atmosphere
(d) frequent absorption of star light by their own atmosphere
Ans: (c)
542. Assertion (A) A dentist uses a concave mirror to examine a small cavity.
Reason (R) A dentist uses a concave mirror which can form a magnified virtual image of an object.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true but R is not a correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
Ans: (a)
543. Chromatic aberration in a lens is caused by
(a) interference (b) diffraction
(c) reflection (d) dispersion
Ans: (d)
544. Light waves projected on oil surface show seven colours due to the phenomenon of
(a) polarisation
(b) refraction
(c) reflection
(d) interference
Ans: (d)
545. The wavelength of visible light are in between
(a) 0.7 mto 1000 m
(b) 0.1 cm to 30 cm
(c) 0.4 mto 0.8 m
(d) 3000 m to 0.4 m
Ans: (c)
546. Line spectrum contains information about
(a) the atoms of the source
(b) the atoms of the prism
(c) the molecules of the source
(d) None of the above
Ans: (a)
547. Consider the following statements
1. Optical fibres are frequently used in telecommunication.
2. A fibre is an optical system based upon the basic principle of total internal reflection.
3. In total internal reflection, the angle of incidence should always be greater than critical angle.
4. The critical angle is very low for a light ray coming from diamond to air.
Which of the statements given above is/are correct?
(a) 1 and 2 (b) Only 2
(c) 3 and 4 (d) All of these
Ans: (d)
548. Consider the following statements
1. For a normal human eye, the least distance of distinct vision of 25 cm.
2. The person suffering of colour blindness cannot distinguish the red and green colours distinctly.
3. The colour blindness depends on various defects of the cylindrical (conical) cell of the retina.
4. The presbyopia affected person uses bifocal lens and cylindrical lens.
Which of the statements given above are correct?
(a) 1, 2, and 4 (b) 2 and 3
(c) 2 and 3 (d) 1, 2, 3 and 4
Ans: (d)
549. In case of a compound microscope which of the following statements is/are correct?
1. The focal length of the eye piece is larger than the focal length of the objective.
2. The focal length of the eye piece is smaller than the focal length of the objective.
3. The image produced in a normal optical microscope is real.
4. The image produced in a normal optical microscope is virtual. Select the correct answer using the code given below.
(a) Only 1 (b) 1 and 4
(c) 2 and 3 (d) 2 and 4
Ans: (b)
Part 15. Electricity and Magnetism
550. The motion of an electron in presence of a magnetic field is depicted in the figure given above. The force acting on the electron will be directed
(a) into the page (b) out of the page
(c) opposite to the motion of the electron
(d) along the motion of the electron
Ans: (b)
551. A person standing 1 m in front of a plane mirror approaches the mirror by 40 cm. The new distance between the person and his image in the plane mirror is
(a) 60 cm (b) 1.2 m (c) 1.4 m (d) 2.0 m
Ans: (b)
552. The upper and lower portions in common type of bi-focal lenses are respectively
(a) concave and convex
(b) convex and concave
(c) both concave of different focal lengths
(d) both convex of different focal lengths
Ans: (a)
553. Which one of the following is used in storage batteries?
(a) Copper (b) Lead (c)Tin (d) Zinc
Ans: (d)
554. A fuse wire is made of
(a) an alloy of tin and copper
(b) an alloy of tin and lead
(c) an alloy of tin and aluminium
(d) an alloy of nickel and chromium
Ans: (b)
555. Conversion of chemical energy into electrical energy occur in
(a) atomic bombs (b) electric heaters
(c) battery (d) dynamo
Ans: (c)
556. In electric supply lines in India, which parameter is kept constant?
(a) Voltage (b) Current
(c) Frequency (d) Power
Ans: (c)
557. Increasing the charge on the plates of a capacitor means
(a) increasing the capacitance
(b) increasing the potential difference between the plates
(c) Both (a) and (b)
(d) None of the above
Ans: (b)
558. What is the most commonly used substance in fluorescent tubes?
(a) Sodium oxide and argon
(b) Sodium vapour and neon
(c) Mercury vapour and argon
(d) Mercury oxide and neon
Ans: (c)
559. Consider the following statements A copper voltameter measures the
1. quantity of current passing through the circuit.
2. amount of copper deposited.
3. resistance of the circuit.
Which of these statements are correct?
(a) 1, 2 and 3 (b) 1 and 2
(c) 2 and 3 (d) 1 and 3
Ans: (b)
560. A simple circuit contains a 12V battery and bulb having 24 ohm resistance. When turn on the switch, the ammeter connected to the circuit would read
(a) 0.5 A (b) 2 A
(c) 4 A (d) 5 A
Ans: (a)
561. Instrument used to store the electric charge is known as
(a) inductor (b) capacitor
(c) transformer (d) transistor
Ans: (b)
562. Imagine a current carrying wire with the direction of current downward or into the page. The direction of magnetic field lines is
(a) clockwise
(b) anti-clockwise
(c) into the page
(d) out of the page
Ans: (a)
563. What is the difference between a CLF and an LED lamp?
1. To produce light, a CLF uses mercury vapour and phosphor while an LED lamp uses semiconductor material.
2. The average life span of a CFL is much longer than of and LED lamp.
3. A CFL is less energy-efficient as compared to an LED lamp.
Which of the statement(s) given above is/are correct?
(a) Only 1 (b) 2 and 3
(c) 1 and 3 (d) 1, 2 and 3
Ans: (c)
564. Which of the following pairs of material serves as electrodes in chargeable batteries commonly used in device such as torch light, electric shaver etc?
(a) Iron and cadmium
(b) Nickel and cadmium
(c) Lead peroxide and lead
(d) Zinc and carbon
Ans: (c)
565. Ohm’s law does not apply to which of the following?
(a) AC circuits (b) Conductors
(c) Semiconductors (d) None of these
Ans: (c)
566. A substance which radiates light when heated to a light temperature is said to be
(a) luminescent (b) incandescent
(c) fluorescent
(d) phosphorescent
Ans: (d)
567. What is the maximum number of different electrical combination possible with three equal resistances?
(a) 2 (b) 3 (c) 4 (d) 5
Ans: (c)
568. Four wires of same material and of dimensions as mentioned below are stretched by a load of same magnitude separately. Which one of them will be elongated maximum?
(a) Wire of 1mlength and 2mmdiameter
(b) Wire of 2 m length and 2 mm diameter
(c) Wire of 5 m length and 105 mm diameter
(d) Wire of 1 m length and 1 mm diameter
Ans: (a)
569. A permanent magnet repels
(a) ferromagnetic substances only
(b) diamagnetic substances only
(c) paramagnetic substances only
(d) Both b and c
Ans: (c)
570. The circuit element where the impressed voltage is always in phase with the resulting current is an ideal
(a) resistor (b) capacitor
(c) coil (d) transformer
Ans: (a)
571. A current carrying wire is known to produce magnetic lines of force around the conducting straight wire. The direction of the lines of force may be described by
(a) left hand thumb rule for up current and right hand thumb rule for down current
(b) right hand thumb rule for up current and left hand thumb rule for down current
(c) right hand thumb rule for both up and down currents
(d) left hand thumb rule for both up and down currents
Ans: (c)
572. In a dry cell (battery), which of the following are used as electrolytes?
(a) Ammonium chloride and zinc chloride
(b) Sodium chloride and calcium chloride
(c) Magnesium chloride and zinc chloride
(d) Ammonium chloride and calcium chloride
Ans: (a)
573. Indiscriminate disposal of used fluorescent electric lamps causes mercury pollution in the environment. Why is mercury used in the manufacture of these lamps?
(a) A mercury coating on the inside of the lampmakes the light bright white
(b) When the lamp is switched ON, the mercury in the lamp causes the emission of ultra-violet radiations
(c) When the lamp is switched on, it is the mercury which converts the ultra-violet energy into visible light
(d) None of the statement given above is correct about the use of mercury in themanufacture of fluorescent lamps
Ans: (b)
574. Three resistors with magnitudes 2, 4 and 8 ohm are connected in parallel. The equivalent resistance of the system would be
(a) less than 2 ohm
(b) more than 2 ohmbut less than 4 ohm
(c) 4 ohm (d) 14 ohm
Ans: (a)
575. A DC voltmeter is capable of measuring a maximum of 300 V. It is used to measure the voltage across a device operating at 220 voltage AC supply, the reading of the voltmeter will be
(a) 300 V (b) 220 V
(c) 110 V (d) Zero
Ans: (d)
576. A straight horizontal conductor carries a steady electric current from south to north. Which one of the following events would happen if a small magnetic compass is placed just above the wire?
(a) The needle remains perpendicular to the conductor
(b) The needle remains parallel to the conductor
(c) The north pole of the needle is deflected towards east
(d) The north pole of the needle is deflected towards west
Ans: (a)
577. A ‘rectifier’ is an electronic device used to convert
(a) AC current into DC current
(b) DC voltage into AC voltage
(c) sinusoidal pulse into square pulse
(d) None of the above
Ans: (a)
578. A positively charged particle projected towards West is deflected towards North by a magnetic field. The direction of the magnetic field is
(a) towards South (b) towards East
(c) in downward direction
(d) in upward direction
Ans: (a)
579. What is the order of magnitude of electric resistance of the human body (dry)?
(a) 102 (b) 104 (c) 106 (d) 108
Ans: (a)
580. Which one of the following is printed on a commonly used fluorescent tube light?
(a) 220 K (b) 273 K
(c) 6500 K (d) 9000 K
Ans: (d)
581. A given conductor carrying a current of 1 ampere produces an amount of heat equal to 2000 J. the current through the conductor is double the amount of heat produced will be
(a) 2000 J (b) 4000 J
(c) 8000 J (d) 1000 J
Ans: (c)
582. Consider the following statements regarding a motor car battery
1. The voltage is usually 12 V.
2. Electrolyte used in hydrochloric acid.
3. Electrodes are lead and copper.
4. Capacity is expressed in ampere hour.
Which of the above statements are correct?
(a) 1 and 2 (b) 2 and 3
(c) 3 and 4 (d) 1 and 4
Ans: (d)
583. Domestic electrical wiring is basically a
(a) series connection
(b) parallel connection
(c) combination of series and parallel connections
(d) series connection within each room and parallel connection elsewhere
Ans: (b)
584. Fluorescent tubes are fitted with a choke. The choke coil
(a) steps up the line voltage
(b) steps-down the line voltage
(c) reduces current in the circuit
(d) chokes low frequency current
Ans: (a)
585. Which one of the following statements about bar magnet is correct?
(a) The pole strength of the North-pole of a bar magnet is larger than that of the South-pole
(b) When a piece of bar magnet is bisected perpendicular to its axis, the North and South poles get separated
(c) When a piece of bar magnet is bisected perpendicular to its axis, two new bar magnets are formed
(d) The poles of a bar magnet are unequal in magnitude and opposite in nature
Ans: (c)
586. Consider the following statements An ordinary light bulb has a rather short life because the
1. filament wire is not uniform.
2. bulb cannot be evacuated completely.
3. wires supporting the filament melt at high temperatures.
Which of the above statements are correct?
(a) 1 and 3 (b) 2 and 3
(c) 1 and 2 (d) 1, 2 and 3
Ans: (b)
587. Which of the following quantities remain constant inastep-downtransformer?
(a) Current (b) Power
(c) Voltage (d) None of these
Ans: (b)
588. Two wires have their lengths, diameters and resistivities all in the ratio of 1 : 2. If the resistance of the thinner wire is 10 , the resistance of the thicker wire is
(a) 5 (b) 10 (c) 20 (d) 40
Ans: (a)
589. Consider the following statements At the present level of technology available in India. Solar energy can be conveniently used to
1. supply hot water to residual buildings.
2. supply water for minor irrigation projects.
3. provide street lighting.
4. electrify a cluster of villages and small towns.
Which of the above statements are correct?
(a) 1, 2, 3 and 4 (b) 3 and 4
(c) 1 and 3 (d) 1, 2 and 3
Ans: (b)
590. Consider the following statements Household electrical appliances are not usually connected in series, because
1. switching of an appliance would switch off the rest.
2. a fuse would blow as soon as one appliance is used.
3. power consumption would be very much greater.
4. the appliances would get damaged due to high current.
Which of the above statements are correct?
(a) 1 only (b) 2 and 3
(c) 3 and 4 (d) 1, 2 and 4
Ans: (a)
591. A charge particle moves with velocity v in a uniform magnetic field B. The magnetic force experienced by the particle is
(a) always zero
(b) zero, if B and v are perpendicular
(c) zero, if B and v are parallel
(d) zero, if B and v are inclined at 45°
Ans: (c)
592. Phase difference between voltage and current in a capacitor in AC circuit is
(a) (b) 0 (c) 2
(d) 3
Ans: (c)
593. In step-down transformer, the AC output gives the
(a) current more than the input current
(b) current less than the input current
(c) current equal to the input current
(d) voltage more than the input voltage
Ans: (a)
594. Which one of the following statements is correct? The space surrounding a charge in uniform motion has
(a) only an electric field
(b) only a magnetic field
(c) Both electric and magnetic fields
(d) Neither an electric field nor a magnetic field
Ans: (c)
595. Assertion (A) In our houses, the current in AC electricity line changes direction 60 times per second.
Reason (R) The frequency of alternating voltage supplied is 50Hz.
(a) Both A and R are individually true and R is the correct explanation of A
(b) Both A and R are individually true and R is not the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true
Ans: (d)
596. Alternating current can be measured by
(a) hot wire ammeter
(b) moving coil galvanometer
(c) tangent galvanometer
(d) None of the above
Ans: (a)
597. Assertion (A) It is not necessary that every bar magnet has one North Pole and one South Pole.
Reason (R) Magnetic poles occur in pair.
Codes
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true, but R is not correct explanation of A
(c) A is true, but R is false
(d) A is false, but R is true
Ans: (d)
598. Ohm’s law defines
(a) a resistance (b) current only
(c) voltage only
(d) both current and voltage
Ans: (a)
599. A current I flows through a potential difference V in an electrical circuit containing a resistance R. The product of V and I i.e., VI may be understood as
(a) resistance R
(b) heat generated by the circuit
(c) thermal power radiated by the circuit
(d) rate of change of resistance
Ans: (c)
600. Lightning conductors are used to protect building from lightning strikes. Which of the following statements is/are true about lightning conductors?
1. Lightning conductors create an electric field at its top so that lightning strikes it preferentially.
2. Lightning conductors reduce the effect of the strike by uniformly distributing the charge (current) over the surface of the building.
3. Lightning conductors take all charge (current) to deep down in the Earth.
4. Lightning conductors must be installed at a place taller than the building. Select the correct answer using the code given below
(a) 1 and 2 (b) 3 and 4
(c) 1, 3 and 4 (d) Only 4
Ans: (b)
601. The inherent property of all matter is/are
(a) diamagnetism (b) paramagnetism
(c) ferromagnetism (d) All of these
Ans: (a)
602. AC power is transmitted from a power house at a high voltages
(a) power cannot be transmitted at low voltages
(b) the rate of transmission is faster at high voltages
(c) it is more economical due to less power loss
(d) a precaution against theft of transmission line
Ans: (c)
603. The core of transformer is laminated to reduce
(a) magnetic loss
(b) eddy current loss
(c) hysteresis loss (d) copper loss
Ans: (b)
604. Fleming right hand rule gives
(a) the magnitude of the magnetic field
(b) the magnitude of the induced emf
(c) the direction of the induced emf
(d) None of the above
Ans: (c)
605. Alternating current instead of direct current is used in long distance electric transmission because
(a) it is easy to generate
(b) rectification is possible
(c) energy loses are minimum
(d) it causes fewer accidents
Ans: (c)
606. Consider the following statements
1. A comb moving through dry hair get electrically charged.
2. Electric lines of force are not closed butmagnetic lines of force are closed.
Which of the statement(s) given above is/are correct?
(a) Only 1 (b) Only 2
(c) Both 1 and 2 (d) Neither 1 nor 2
Ans: (c)
607. A choke coil has
(a) low inductance and high resistance
(b) low inductance and low resistance
(c) high inductance and low resistance
(d) high inductance and high resistance
Ans: (c)
608. When an AC source is connected across a resistor
(a) the current lags behind the voltage in phase
(b) the current and the voltage are in same phase
(c) the current leads the voltage in phase
(d) None of the above
Ans: (b)
609. The Dynamo converts
(a) mechanical energy into electrical energy
(b) electrical energy into mechanical energy
(c) mechanical energy into magnetic
(d) None of the above
Ans: (a)
610. The electric field inside a perfectly conducting hollow object is
(a) 4
(b) infinite (c) zero
(d) dependent upon the shape of the object
Ans: (c)
611. All the magnetic materials lose their magnetic properties when
(a) dipped in oil (b) dipped in water
(c) strongly heated
(d) brought near a i.e. of iron
Ans: (c)
612. Which one of the following is not made of soft iron?
(a) Core of dynamo
(b) Core of transformer
(c) Electromagnet
(d) Magnet of loudspeaker
Ans: (d)
613. The core of an electromagnet is made of soft iron because soft iron has
(a) large density and large retentivity
(b) small density and large retentivity
(c) large susceptibility and small retentivity
(d) small susceptibility and small retentivity
Ans: (c)
614. Match the following lists
List I List II (Type of Cells) (Electro motive Force)
A. Voltaic cell 1. 1.50 V
B. Dry cell 2. 2.00 V
C. Lead container cell 3. 1.08 V
D. Battery of six cells 4. 12.00 V
Codes A B C D A B C D
(a) 1 2 3 4 (b) 3 1 2 4
(c) 4 3 2 1 (d) 3 4 2 1
Ans: (b)
615. Two pieces of conductor of same material and of equal length are connected in series with a cell. One of the two pieces has cross-sectional area double that of the other. Which one of the following statements is correct in this regard?
(a) The thicker one will allow stronger current to pass through it.
(b) The thinner one would allow stronger current to pass through it.
(c) Same amount of electric current would pass through both the pieces producingmore heat in the thicker one.
(d) Same amount of electric current would pass through both the pieces producing more heat in the thinner one.
Ans: (d)
616. The temperature at which a ferromagnetic material becomes paramagnetic is called
(a) Curie temperature
(b) neutral temperature
(c) inversion temperature
(d) critical temperature
Ans: (a)
617. Electricity is produced through dry cell from
(a) chemical energy
(b) thermal energy
(c) mechanical energy
(d) nuclear energy
Ans: (a)
618. Consider the following statements
1. Magnetic lines of force are closed curves while electric lines are not.
2. Electric lines of force are closed curves while magnetic lines are not.
3. Both electric and magnetic lines of force are closed curves. Which of statement(s) given above is/are correct?
(a) Only 2 (b) Both 1 and 2
(c) Only 1 (d) 1, 2 and 3
Ans: (c)
619. Consider the following statements
1. The susceptibility of a paramagnetic material varies inversely as the temperature.
2. The susceptibility of a diamagnetic material is small and negative.
3. The relative permeability of a diamagneticmaterial is less than unity.
4. The relative permeability of a paramagnetic material is greater than unity.
Which of the statements given above are correct?
(a) 1, 2 and 3 (b) 2, 3 and 4
(c) 1, 3 and 4 (d) 1, 2, 3 and 4
Ans: (d)
620. Consider the following statements A magnetic field
1. never exerts a force on a charged particle.
2. always exerts a force on a changed particle.
3. exerts a force on a charged particle if it is moving across the magnetic lines of force.
4. exerts a force on a charged particle if it is moving along the magnetic lines of force.
Which of the statement(s) given above is/are correct?
(a) Only 3 (b) Only 4
(c) 1 and 2 (d) 1, 2, 3 and 4
Ans: (a)
621. Consider the following sentences
1. In ordinary bulbs only 5% to 10% electrical energy is converted into light energy.
2. Tungsten has very high melting point as 3422°C, the filament of bulb is made of it.
3. Themica has good electrical resistance.
4. The electric bulb was first invented by Thomas Alva Edison.
Which of the above statements are correct?
(a) 1 and 3 (b) 3 and 4
(c) All of these (d) None of these
Ans: (c)
622. A device, which is used in our TV set, Computer, Radio set for storing the electric charge, is
(a) resistor (b) inductor
(c) capacitor (d) conductor
Ans: (c)
623. Consider the following statements
1. Ohm’s law is not applicable at very low and very high temperature.
2. Ohm’s law is applicable to semiconductor.
3. Ohm’s law is not applicable to electron tubes, discharge tubes and electrolytes.
4. Conductance is the reciprocal of resistance and is measured in siemens.
Which of the statements given above are correct?
(a) 1, 2 and 3 (b) 1, 2 and 4
(c) 1, 3 and 4 (d) 1, 2, 3 and 4
Ans: (c)
624. When a positively charged conductor connected to the earth, then
(a) electrons flow from the conductor to the earth
(b) protons flow from the conductor to the earth
(c) electrons flow from earth to the conductor
(d) no charge flow occurs
Ans: (c)
625. Consider the following statements
1. A galvanometer is converted into an ammeter when we connect a low resistance in parallel.
2. A galvanometer is converted into a voltmeter when we connect a high resistance in series.
3. The conductivity of superconductor is infinite.
Which of the above statement(s) given above is/are correct?
(a) Only 1 (b) Only 2
(c) 2, and 3 (d) 1, 2 and 4
Ans: (d)
626. According to Coulomb’s law, the electrostatic force between two charges is
(a) directly proportional to the cube of the distance between charges
(b) inversely proportional to the product of the charges
(c) inversely proportional to the square of the distance between the charges
(d) None of the above
Ans: (c)
627. Consider the following statements
1. Au, Ag, Cu, Zn, Sb, Bi, H2O and air are examples of diamagnetic.
2. Na, Al, Mn, CaCl2 and oxygen are examples of paramagnetic.
3. Fe, Co, Ni and Fe3O4 are examples of ferromagnetic.
Which of the statement(s) given above is/are correct?
(a) 1 only (b) 2 only
(c) 2 and 3 (d) 1, 2 and 3
Ans: (d)
628. Consider the following statements
1. The resistance of ideal voltmeter is infintie.
2. The resistance of ideal ammeter is zero.
3. Tangent galvanometer is used to measure steady currents.
4. Law of electrolysis is given by Faraday.
Which of the statements given above are correct?
(a) 1, 2 and 3
(b) 1, 2 and 4
(c) 2, 3 and 4
(d) 1, 2, 3 and 4
Ans: (d)
629. The Current (I)-Voltage (V) plot of a certain electronic device is given above.The device is
(a) a semiconductor
(b) a conductor which obeys Ohm’s law
(c) a superconductor
(d) an insulator
Ans: (b)
630. Light Emitting Diode (LED) converts
(a) light energy into electrical energy
(b) electrical energy into light energy
(c) thermal energy into light energy
(d) mechanical energy into electrical energy
Ans: (b)
631. Two charges of 40 C and 20 C are kept some distance apart. Now, they are touched and kept at the same distance apart. The ratio of the initial and the final forces between them is
(a) 1 : 8 (b) 8 : 1 (c) 1 : 1 (d) 4 : 1
Ans: (b)
632. The electric current passing through a metallic wire produces heat because of
(a) collision of the atoms of the metal with each other
(b) collision of the conduction electron with the atoms of the metallic wire
(c) collision of conduction electrons with each other
(d) None of the above
Ans: (c)
633. Consider the following statements
1. Constantan wire is used in making standard resistance because its temperature co-efficients of resistance is negligible.
2. Thermocouple thermometer is based on Peltier effect.
3. Potentiometer measures potential more accurately because it measures potential in the open circuit.
4. In an electrolysis, the amount of mass deposited or liberated at an electrode is directly proportional to amount of charge.
Which of the statements given above are correct?
(a) 1, 2, and 3 (b) 1, 3 and 4
(c) 2, 3 and 4 (d) 1, 2, 3 and 4
Ans: (d)
634. Consider the following statements
1. A thermoelectric refrigerator works on Peltier effect.
2. The electrolyte in the dry cell is ammonium chloride.
3. The electrolyte in a car battery is sulphuric acid.
4. When a metal is heated, its resistance increases.
Which of the statements given above are correct?
(a) 1, 2 and 3 (b) 2, 3 and 4
(c) 1, 2 and 4 (d) 1, 2, 3 and 4
Ans: (c)
635. Which of the adjoining graph represent ohmic resistance?
Ans: (a)
636. The phenomenon of electromagnetic induction implies a production of induced
(a) resistance in a coil when the magnetic field changes with time
(b) current in a coil when an electric field changes with time
(c) current in a coil when a magnetic field changes with time
(d) voltage in a coil when a electric field with time
Ans: (b)
637. Two long wires each carrying a DC current in the same direction are placed close to each other. Which one of the following statements is correct?
(a) The wires will attract each other
(b) The wires will repel each other
(c) There will be no force between the wires.
(d) There will be a force between the wires only at the moment when the current is switched ON or OFF.
Ans: (a)
Part 16. Modern Physics
638. Heavy water is used as a moderator in a nuclear reactor. The function of the moderator is
(a) to control the energy released in the reactor
(b) to absorb neutrons and stop the chain reaction
(c) to cool the reactor
(d) to slow down the neutrons to thermal energy
Ans: (d)
639. A semiconducting device is connected in a series circuit with a battery and a resistance.Current is found to pass through the circuit. If the polarity of the battery is reversed, the current drops to zero. The device may be
(a) p-type semiconductor
(b) n-type semiconductor
(c) an intrinsic semiconductor
(d) p-n junction
Ans: (c)
640. Confirmation of the presence of Higgs Boson will justify
(a) both the standard model and superstring theory
(b) the unification of all the four fundamental forces
(c) the steady-state model of the universe
(d) themass of the fundamental particles
Ans: (a)
641. Consider the following statements
1. Plutonium-239 can be made artificially.
2. Boron is used in a nuclear reactor to absorbs unwanted neutrons.
3. In nature, the availability of uranium-238 is much more than that of uranium-235.
Which of these statement(s) is/are correct?
(a) Only 1 (b) 1 and 2
(c) 1, 2 and 3 (d) Only 3
Ans: (c)
642. Consider the following statements
1. An atom bomb is based upon the principle of nuclear fission.
2. Hydrogen bomb is based upon the principle of nuclear fusion.
3. Nuclear reactor is based upon the principle of controlled nuclear fission.
Which of the statement(s) given above is/are correct?
(a) Only 1 (b) Only 3
(c) 1 and 2 (d) 1, 2 and 3
Ans: (d)
643. If a U238 nucleus splits into two identical parts, the two nuclei so produced will be
(a) radioactive (b) stable
(c) isotopes (d) isobars
Ans: (b)
644. Match List I (Particle) with List II (Approximate Rest Energy in MeV) and select the correct answer using the codes gives below the lists.
List I List II
A. Electron 1. 940
B. Neutrino 2. 140
C. Neutron 3. 0.5
D. Pi-Meson 4. 0
Codes A B C D A B C D
(a) 2 4 1 3 (b) 3 4 1 2
(c) 3 1 4 2 (d) 2 1 4 3
Ans: (b)
645. A nuclear reactor harnesses nuclear energy by
(a) nuclear fusion
(b) spontaneous fission
(c) uncontrolled chain reaction
(d) controlled chain reaction
Ans: (d)
646. Consider the following metals
1. Uranium 2. Radium
3. Plutonium
Which of these are used in making nuclear weapons?
(a) 1 and 2 (b) 1, 2 and 3
(c) 2 and 3 (d) 1 and 3
Ans: (d)
647. Consider the following statements
1. In a semiconductor, the uppermost band is the valence band.
2. All semiconductors are electrically neutral.
3. With increase of temperature, the resistivity of a semiconductor decreases.
4. Addition of a small amount of impurity of a III or V group elements to a pure semiconductor increases its resistivity. Choose the correct statements.
(a) 1 and 2 (b) 2 and 3
(c) 3 and 4 (d) 1 and 4
Ans: (b)
648. If a proton of mass m is moving with the velocity of light, its mass will be
(a) unchanged (b) large but finite
(c) infinite (d) zero
Ans: (c)
649. The mass-energy relation is the out come of
(a) quantum theory
(b) general theory of relativity
(c) field theory of relativity
(d) special theory of relativity
Ans: (d)
650. In an observation α-particles, -particles and -rays have same energies. Their penetrating power in a given medium in increasing order will be
(a) α, , (b) , , α(c) α, , (d) , α,
Ans: (a)
651. Consider the following statements
1. According to de-Broglie hypothesis particle have wave-like characteristics.
2. When an electron and proton have the same de-Broglie wavelength, they will have equal momentum.
Which of the statement(s) given above is/are correct?
(a) Only 1 (b) Only 2
(c) Both 1 and 2 (d) Neither 1 nor 2
Ans: (c)
652. Consider the following statements in a nuclear reactor, self sustained chain reaction is possible because
1. more neutrons are related in each of the fission reaction.
2. the neutrons immediately take part in the fission process.
3. the fast neutrons are slowed down by graphite.
4. every neutron released in the fission reaction initiates fission.
Which of these statements are correct?
(a)1, 2 and 3 (b) 1 and 3
(c) 2 and 4 (d) 2, 3 and 4
Ans: (d)
653. In black and white televisions, pictures on the screen are produced due to bombardment of
(a) X-rays photons on a white screen
(b) X-rays photons on a white fluorescent screen
(c) electrons on a white screen
(d) electrons on a fluorescent white screen
Ans: (d)
654. What is the difference between bluetooth and Wi-Fi devices?
(a) Bluetooth used 2.4 GHz radio frequency band whereas Wi-Fi can use 2.4 GHz or 5 GHz frequency band
(b) Bluetooth is used for wireless local area networks (WLAN) only. Whereas Wi-Fi is used for wireless wide area networks (WWAN) only
(c) When information is transmitted between two-devices using bluetooth technology, the devices have to be in the line of sight of each other, but when Wi-Fi technology is used the devices need not be in the line of sight of each other
(d) The statements (a) and (b) given above are correct in this context
Ans: (c)
655. Particles which can be added to the nucleus of an atom without changing its chemical properties are
(a) electrons (b) protons
(c) neutrons (d) α-particles
Ans: (c)
656. The known forces of nature can be divided into four classes, viz, gravity, electromagnetism, weak nuclear force and strong nuclear force. With reference to them, which one of the following statements is not correct?
(a) Gravity is the strongest of the four
(b) Electromagnetism acts only on particles with an electric charge
(c) Weak nuclear force causes, radioactivity
(d) Strong nuclear force holds protons and neutrons inside the nucleus of an atom
Ans: (a)
657. Fusion reaction takes place at high temperature because
(a) nuclei break up at high temperature
(b) atoms are ionized at high temperature
(c) molecules break up at high temperature
(d) kinetic energy is high enough to overcome repulsion at high temperature
Ans: (d)
658. Curie is a unit of
(a) energy of gamma rays
(b) half-life
(c) radioactivity
(d) intensity of gamma rays
Ans: (c)
659. In nuclear reactor, cadmium rods are used to
(a) absorb neutorns
(b) produce neutrons
(c) slow down neutrons
(d) speed up neutrons
Ans: (a)
660. An oscilloscope is an instrument which allows us to see waves produced by
(a) visible light (b) X-rays
(c) sound (d) gamma rays
Ans: (a)
661. Long distance short wave radio broad casting uses
(a) direct wave (b) sky wave
(c) ionospheric wave (d) ground wave
Ans: (c)
662. Cosmic rays
(a) are charged particles
(b) are uncharged particles
(c) can be charged as well as uncharged.
(d) None of the above
Ans: (a)
663. The technique of collecting information about an object from a distance without making physical contact with it is
(a) space shuttle
(b) remote control
(c) remote accessing
(d) remote sensing
Ans: (d)
664. Intelsat satellite is used for
(a) radar communication
(b) radio communication
(c) intercontinental communication
(d) None of the above
Ans: (c)
665. Modem is a device used for
(a) converting analog signals to digital signals
(b) modulating signals
(c) either of the above
(d) None of the above
Ans: (a)
666. Match the following lists
List I List II
A. Germanium at 0 K 1. n-type semiconductor
B. Germanium at room temperature 2. p-type semiconductor
C. Germanium doped with indium 3. Insulator
D. Germanium doped with arsenic 4. Intrinsic Semiconductor
Codes A B C D A B C D
(a) 1 2 3 4 (b) 4 3 2 1
(c) 3 4 2 1 (d) 4 3 1 2
Ans: (c)
667. Compton effect is associated with
(a) positive rays (b) -rays
(c) X-rays (d) -rays
Ans: (c)
668. Cathode rays are similar to visible light rays, in that
(a) they both can ionise the gas through which they pass
(b) they both have a definite magnitude of wavelength
(c) they both can affect photographic plates
(d) they both can be deflected by electric and magnetic fields
Ans: (c)
-rays are deflected by
(a) a magnetic field but not by an electric field
(b) an electric field but not by a magnetic field
(c) both electric and magnetic field
(d) neither an electric field nor magnetic field
Ans: (d)
670. Consider the following statements
1. The strongest force in the nature is nuclear force.
2. Atomic power plant works on the principle of fission.
3. Cadmium is not a radioactive element.
4. Einstein’s mass-energy relation is given by the expressionE = mc2
Which of the statements given above are correct?
(a) 1, 2 and 3
(b) 2, 3, and 4
(c) 1, 2 and 4
(d) 1, 2, 3, and 4
Ans: (d)
671. Photoelectric effect can be explained by assuming that light
(a) can be polarised
(b) consist of quanta
(c) is a form of transverse wave
(d) is a form of longitudinal wave
Ans: (b)
672. Consider the following statements
1. Nuclear forces are spin dependent.
2. The fourth state of matter is known as plasma.
3. Nuclear forces are attractive or repulsive depending upon separation between nucleons.
4. The main source of solar energy is nuclear fusion.
Which of the statements given above are correct?
(a) 1, 2 and 3
(b) 2, 3 and 4
(c) 1, 2 and 4
(d) 1, 2, 3 and 4
Ans: (c)
673. PSLV-C14 in its latest space quest had carried Oceansat-2 with how many foreign nano-satellites?
(a) 5 (b) 6
(c) 7 (d) 9
Ans: (b)
674. The electrons are emitted in the photoelectric effect from a metal surface
(a) only if the temperature of the surface is high
(b) only if the frequency of the incident radiation is above a certain threshold value
(c) at the rate of independent of the nature of the metal
(d) None of the above
Ans: (b)
675. Assertion (A) A dish antenna is highly directional.
Reason (R) This is because a dipole antenna is omni directional.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true, but R is not the correct explanation of A
(c) A is true, but R is false
(d) A is false, but R is true
Ans: (b)
676. Assertion (A) Short wave based are used for transmission of radio waves to a large distance.
Reason (R) Short waves are reflected from ionosphere.
(a) Both A and R are true and R is the correct explanation of A
(b) Both A and R are true, but R is not the correct explanation of A
(c) A is true, but R is false
(d) A is false, but R is true
Ans: (a)
677. When X-rays are produced, then
(a) heat is produced on the target
(b) heat is absorbed by the target
(c) a luminous light is to be seen on the target.
(d) Both (a) and (c)
Ans: (d)
678. X-rays are electromagnetic radiation whose wavelengths are of the order or
(a) 1 m (b) 10–1 m
(c) 10–5 m (d) 10–10 m
Ans: (d)
679. Which of the following is used in oven?
(a) X-rays (b) UV-rays
(c) Microwaves (d) Radio waves
Ans: (c)
680. In an atomic explosion, release of large amount of energy is due to conversion of
(a) chemical energy into nuclear energy
(b) nuclear energy into heat
(c) mass into energy
(d) chemical energy into heat
Ans: (c)
681. A radar beam consists of
(a) X-rays (b) ultraviolet rays
(c) infrared rays (d) microwaves
Ans: (d)
682. Consider the following statements X-rays
1. can pass through thin sheets of aluminium.
2. can be deflected by magnetic field.
3. move with a velocity less than the velocity of ultraviolet rays in vacuum.
Which of the statement(s) given above is/are correct?
(a) 1, 2 and 3 (b) Only 1
(c) 2 and 3 (d) 1 and 2
Ans: (b)
683. Consider the following statements
1. A geostationary satellite is at an approximate height of 10,000 km.
2. FM transmission of music is a very good quality because the atmospheric or mass made noises which are generally frequency variations can do little harm.
Which of the statement(s) given above is/are correct?
(a) Only 1 (b) Only 2
(c) Both 1 and 2 (d) Neither 1 nor 2
Ans: (b)
684. Consider the following statements
1. X-rays show transverse wave characteristics
2. X-rays can eject electrons from certain metal surfaces.
3. X-rays of 0.1 Å are harder than X-rays of 0.2Å
Which of the statement(s) given above is/are correct?
(a) Only 1
(b) 1 and 2
(c) 2 and 3
(d) 1, 2 and 3
Ans: (d)
685. Which of the following statements are true?
1. All radioactive elements decay exponentially with time.
2. Half-life time of radioactive element is the time required for one-half of the radioactive atoms to disintegrate.
3. Age of the earth can be determined by radioactive dating.
4. Half-life time of a radioactive element is fifty percent of its average life period. Select the correct answer using the codes given below.
(a) 1 and 2 (b) 1, 3 and 4
(c) 1, 2 and 3 (d) 2 and 3
Ans: (c)
686. Penetrating power of X-rays does not depend on
(a) potential difference
(b) wavelength (c) energy
(d) current in the filament
Ans:
(d)
687. It is possible to understand nuclear fission on the basis of the
(a) meson theory of the nuclear forces
(b) proton-proton cycle
(c) independent particle model of the nucleus
(d) liquid drop model of nucleus
Ans: (d)
688. Consider the statements
1. Photon is a particle of light.
2. Mass of photon is not defined.
3. Speed of photon is as the speed of light.
4. Photons are charged. Which options is/are correct?
(a) 1 and 2 (b) 1, 2, 3 and 4
(c) 1, 2 and 3 (d) 1 and 3
Ans: (c)
689. X-rays can be produced
(a) when low speed electrons is ejected
(b) when high speed electron is obstructed by a metal surface
(c) when anode-ray obstructed by a solid object
(d) when -ray is obstructed by a solid object
Ans: (b)
690. If alpha, beta and gamma rays carry same momentum, which has the longest wavelength?
(a) Beta rays (b) Alpha rays
(b) Gamma rays
(d) All have same wavelength
Ans: (d)
691. Consider the following statements
1. The fusion of hydrogen into helium is more likely to take place at high temperature and high pressure.
2. Energy generation in stars is mainly due to fusion of light nuclei.
3. Neutrino is a particle which has no charge but has spin.
4. Nucleon is a common name for electron and neutron.
Which of the statement(s) given above are correct?
(a) 1, 2 and 4 (b) 2, 3 and 4
(c) 1, 3 and 4 (d) 1, 2 and 3
Ans: (d)
692. In photoelectric effect, the number of photo electrons emitted is proportional to
(a) velocity of incident beam
(b) work function of photo cathode
(c) frequency of incident beam
(d) intensity of incident beam
Ans: (d)
693. The fuel used in nuclear power plants is
(a) U-235 (b) U-238
(c) U-236 (d) U-239
Ans: (a)
694. Consider the following statements
1. Alpha rays emitted from a radioactive substance are helium nuclear.
2. Beta rays emitted by radioactive substance are charged particles emitted by the nucleus.
3. Gamma rays are electromagnetic waves.
4. The nuclear force is a short range force.
Which of the statements given above are correct?
(a) 1, 2 and 3 (b) 2, 3 and 4
(c) 1, 2 and 4 (d) 1, 2, 3 and 4
Ans: (d)
695. In a discharge tube, ionization of enclosed gas is produced due to collisions between
(a) negative electrons and neutral atoms/molecules
(b) photons and neutral atoms/molecules
(c) neutral gas atoms/molecule
(d) positive ions and neutral atoms/molecules
Ans: (a)
696. Which of the following is not the property of cathode rays?
(a) It casts shadow
(b) It produces fluorescence
(c) It does not deflect in electric field
(d) It produces heating effect
Ans: (c)
697. A transistor is made of
(a) a metal piece sandwiched between two intrinsic semiconductors
(b) doped semiconductor
(c) intrinsic semiconductor
(d) None of the above
Ans: (b)
698. With rise of temperature, the specific resistance of semiconductor
(a) decreases (b) increases
(c) remains unchanged
(d) None of the above
Ans: (a)
699. When arsenic is added as an impurity to silicon, the resulting material is
(a) p-type semiconductor
(b) n-type semiconductor
(c) n-type conductor
(d) None of the above
Ans: (b)
700. A diode can be used for
(a) detection (b) amplification
(c) rectification (d) modulation
Ans: (c)
701. The sky wave propagation is suitable for radio waves of frequency
(a) from 2MHz to 20 MHz
(b) from 2MHz to 30 MHz
(c) from 2MHz to 80 MHz
(d) up to 2MHz
Ans: (b)
702. A pure semiconductor has
(a) a finite resistance which decreases with temperature
(b) a finite resistance which increases with temperature
(c) a finite resistance which does not depend upon temperature
(d) on finite resistance at 0°C
Ans: (a)
703. Optical fibre communication is generally preferred over general communication system because
(a) of signal security
(b) it is more efficient
(c) Both a and b
(d) None of the above
Ans: (c)
704. The electrical circuits used to get smooth DC output from a rectified circuit is called
(a) amplifier (b) filter
(c) oscillator (d) full wave rectifier
Ans: (b)
705. In a p-type semiconductor
(a) electrons are the only carriers
(b) holes are the only carriers
(c) holes are the majority carriers and electrons are the minority carriers
(d) None of the above
Ans: (c)
706. The absorption of radio waves by the atmosphere depends on
(a) their frequency
(b) the polarisation of the wave
(c) their distance from the transmitter
(d) the polarisation of the atmosphere
Ans: (a)
707. Which of the following satellites is used in ship-to-shore and shore-to-shore and shore-to-ship communication?
(a) Marisat (b) Comsat
(c) Telestar (d) Intelsat
Ans: (a)
708. Intelsat satellite works as a
(a) transmitter (b) absorber
(c) repeater (d) None of these
Ans: (c)
709. The audio signal
(a) possess very high frequency
(b) canbe sent directly over the air for distance
(c) cannot be sent directly over the air for large distance
(d) None of the above
Ans: (c)
710. For television broadcasting the frequency employed is normally
(a) 30-300 kHz (b) 30-300 GHz
(c) 30-300 Hz (d) 30-300 MHz
Ans: (d)
711. Cathode rays are made up of electrons. Anode rays are made up of
(a) protons and positrons only
(b) protons only
(c) all positive particles of atom
(d) positive residence of atom
Ans: (d)
712. The frequency band used for radar relay systems and television is
(a) VLF (b) UHF
(c) VHF (d) EHF
Ans: (b)
713. Modern communication systems use
(a) digital circuits
(b) analog circuits
(c) combination of analog and digital circuits
(d) None of the above
Ans: (a)
714. Through which mode of propagation the radio waves can be sent from one place to another
(a) space wave propagation
(b) sky wave propagation
(c) ground wave propagation
(d) All of the above
Ans: (d)
715. Which of the following statements is correct?
(a) Two isobars always have the same mass number
(b) Two isotopes always have the same mass number
(c) Two isotones always have same mass number
(d) Two isobars always have same atomic number
Ans: (a)
716. Canal rays are
(a) positive ray
(b) negative ray
(c) neutral
(d) None of the above
Ans: (a)
717. Resistivity of semiconductor depends on
(a) length of semiconductor
(b) shape of semiconductor
(c) atomic nature of semiconductor
(d) shape and atomic nature of semiconductor
Ans: (c)
718. Consider the following statements
1. The size of atom is of the order of 10–10m.
2. The size of atomic nucleus is of the order of 10–15m.
3. The electron emitted in beta radiation originates from decay of a neutron in a nucleus.
Which of the statements given above is/are correct?
(a) Only 1 (b) Only 2
(c) 1 and 3 (d) 1, 2 and 3
Ans: (d)
719. The -ray in a radioactive disintegration is similar to
(a) cathode ray (b) anode ray
(c) α-ray (d) -ray
Ans: (a)
720. The efforts to detect the existence of Higgs Boson particle have become frequent in news in the recent past.What is/are the importance/importances of discovering this particle?
1. It will enable us to understand as to why elementary particles have mass.
2. It will enable us in the near future to develop the technology of transferring matter from one point to another without traversing the physical space between them.
3. It will enable us to create better fuels for nuclear fission. Select the correct answer using the codes given below
(a) Only 1 (b) 2 and 3
(c) 1 and 3 (d) All of these
Ans: (a)
721. Range of wavelength between range of wavelength of ultraviolet rays and infrared rays is
(a) 8800 Å to 9800 Å
(b) 3000 Å to 7000 Å
(c) 380 nm to 780 nm
(d) 3800 nm to 7800 nm
Ans: (c)
722. An n-type semi conductor is
1. positively charged
2. negatively charged
3. neutral (electrically)
4. charged depends upon its biasing Which statement—s is/are correct?
(a) Only 2 (b) 2 and 4
(c) Only 3 (d) Only 4
Ans: (c)
723. Doping of semiconductor
1. increases its conductivity
2. decreases its conductivity
3. increases its resistivity
4. decreases its resistivity Which option is correct?
(a) Only 1 (b) Only 2
(c) 2 and 3 (d) 1 and 4
Ans: (d)
724. Principle of Hydrogen Bomb is based on
(a) nuclear fission
(b) nuclear Radioactive disintengration
(c) Nuclear fusion
(d) either nuclear fission or nuclear fusion
Ans: (c)
725. Which ray have the highest speed?
(a) α-ray
(b) -ray
(c) -ray
(d) Cathode ray
Ans: (c)
726. For a given Light wave incident on metal surface kinetic energy of photo electron
(a) depends on the work function for the metal
(b) does not depend on the work function for the metal
(c) depends on the intensity of light
(d) Only (a) and (c) are correct
Ans: (a)