1. A body is allowed to slide on a frictional less track from rest under-gravity. The track ends in a circular

loop of diameter D. What should be the minimum height of the body in terms of D, so that it may

successfully complete the loop?

(a) D

(b) D

(c) D

(d) 2D

2. A body is moving along a circular path with variable speed. It has

(a) a radial acceleration

(b) a tangential acceleration

(c) zero acceleration

(d) both tangential and radial accelerations

3. A body is traveling in a circle at constant speed. It

(a) has constant velocity.

(b) has no acceleration

(c) has an inward acceleration

(d) has an outward radial acceleration

4. A body of mass 100 gram, tied at the end of a string of length 3 m rotates in a vertical circle and is just

able to complete the circle. If the tension in the string at its lowest point is 3.7 N, then its angular

velocity will be ______ (g = 10 m/s2)

(a) 4 rad/s

(b) 3 rad/s

(c) 2 rad/s

(d) 1 rad/s

5. A body of mass 500 gram is rotating in a vertical circle of radius 1 m. What is the difference in its

kinetic energies at the top and the bottom of the circle?

(a) 4.9 J

(b) 19.8 J

(c) 2.8 J

(d) 9.8 J

6. A body of mass m is suspended from a string of length l. What is the minimum horizontal velocity that

should be given to the body in its lowest position so that it may complete full revolution in the vertical

plane with the point of suspension at the center of circle?

(a)

(b)

(c)

(d)

7. A body of mass m performing UCM with frequency n along the circumference of circle having radius r,

force is given by

(a) 4nm2

(b) 42n2m

(c) 2n2mr

(d) nm2

8. A bucket containing water is tied to one end of a rope of length 2.5 m and rotated about the other

end in a vertical circle. What should be the minimum velocity of the bucket at the highest point, so that

the water in the bucket will not spill? (g = 10 m/s2)

(a) 2.5 m/s

(b) 4 m/s

(c) 5 m/s

(d) 7 m/s

9. A bucket tied at the end of a 1.6 m long string is whirled in a vertical circle with a constant speed.

What should be the minimum speed so that the water from the bucket does not spill when the bucket is

at the highest position?

(a) 4 m/sec.

(b) 6.25 m/sec.

(c) 16 m/sec.

(d) None of these

10. A can filled with water is revolved in a vertical circle of radius 4 metre and the water does not fall

down. The time period of revolution will be

(a) 1 sec

(b) 10 sec

(c) 8 sec

(d) 4 sec

11. A car has a linear velocity v on a circular track of radius r. If its speed is increasing at a rate of a m/s2,

then its resultant acceleration will be

(a)

(b)

(c)

(d)

12. A car is moving in a circular track of radius 10 metre with a constant speed of 10 m/sec. A plumb bob

is suspended from the roof of the car by a light rigid rod of 1 metre long. The angle made by the rod with

the track is

(a) zero

(b) 30

(c) 45

(d) 60

13. A car is moving in horizontal circular track of radius 10 m, with a constant speed of 36 km/hour. A

simple pendulum is suspended from the roof of the car. If the length of the simple pendulum is 1 m,

what is the angle made by the string with the track?

(a) 30

(b) 45

(c) 60

(d) 90

14. A car is moving on a circular path and takes a turn. If R1 and R2 are the reactions on the inner and

outer wheels respectively, then

(a) R1 = R2

(b) R1 < R2

(c) R1 > R2

(d) R1 R2

15. A car is moving with a speed of 30 m/s on a circular path of radius 500 m. Its speed is increasing at

the rate of 2 m/s2. The acceleration of the car is

(a) 9.8 m/ s2

(b) 1.8 m/2

(c) 2 m/s2

(d) 2.7 m/s2

15. A car moving on a horizontal road may be thrown out of the road is taking a turn

(a) by the gravitational force

(b) due to the lack of proper centripetal force

(c) due to the lack of frictional force between the tire and the road

(d) due to the reaction of the ground

17. A car of mass 1000 kg moves on a circular road with a speed of 20 m/s. Its direction changes by 90

after traveling 628 m on the road. The centripetal force acting on the car is

(a) 500 N

(b) 1000 N

(c) 1500 N

(d) 2000 N

18. A car of mass 800 kg moves on a circular track of radius 40 m. If the coefficient of friction is 0.5, then

maximum velocity with which the car can move is

(a) 7 m/s

(b) 14 m/s

(c) 8 m/s

(d) 12 m/s

19. A car sometimes overturns while taking a turn. When it overturns, it is

(a) the inner wheel which leaves the ground first

(b) the outer wheel which leaves the ground first

(c) both the wheel leave the ground simultaneously

(d) either inner wheel or the outer wheel leaves the ground

20. A coin kept on a rotating gramophone disc just begins to slip if its centre is at a distance of 8 cm from

the centre of the disc. The angular velocity of the gramophone disc is then doubled. Through what

distance, the coin should be shifted towards the centre, so that the coin will just slip?

(a) 2 cm

(b) 4 cm

(c) 6 cm

(d) 16 cm

21. A cyclist goes round a circular path of circumference 343 m in s. The angle made by him, with the

vertical is

(a) 42

(b) 43

(c) 44

(d) 45

22. A cyclist is moving in a circular track of radius 80 m, with a velocity of 36 km/hour. In order to keep

his balance, he has to lean inwards from the vertical through an angle . If g = 10 m/s2, then q is given by

(a) tan1 (2)

(b) tan1 (4)

(c) tan1

(d) tan1

23. A cyclist turns around a curve at 15 miles per hour. If he turns at double the speed, the tendency of

overturn is

(a) doubled

(b) quadrupled

(c) halved

(d) unchanged

24. A fighter aeroplane flying in the sky dives with a speed of 360 km/hr in a vertical circle of radius 200

m. Weight of the pilot sitting in it is 75 kg. What will be the value of force with which the pilot presses

his seat when the aeroplane is at highest position (g = 10 m/ s2)

(a) 3000 N

(b) 1500 N

(c) (75 g)N

(d) 300 N

25. A frictional track ABCDE ends in a circular loop of radius R, body slides down the track from point A

which is at a height h of 5 cm. Maximum value of R for the body to successfully complete the loop is:

(a) 5 cm

(b) cm

(c) cm

(d) 2 cm

Ans. 1 to 25

1. B

2. D

3. C

4. B

5. D

6. D

7. B

8. C

9. A

10. D

11. A

12. C

13. B

14. B

15. D

16. C

17. B

18. B

19. A

20. A

21. D

22. D

23. B

24. B

25. D

26. A thief stole a box with valuable article of weight W and jumped down a wall of height h. Before he

reach the ground he experienced a load of

(a) zero

(b) W / 2

(c) W

(d) 2 W

27. The acceleration due to gravity g and mean density of the earth r are related by which of the

following relation? Where g is gravitational constant and R is radius of the earth

(a) =

(b) =

(c) =

(d) =

28. When the planet comes nearer the sun moves

(a) fast

(b) slow

(c) constant at every point

(d) none of the above

294. Keplers second law regarding constancy of arial velocity of a planet is a consequence of the law of

conservation of

(a) energy

(b) angular momentum

(c) linear momentum

(d) none of these

30. The period of geostationary artificial satellite is

(a) 24 hours

(b) 6 hours

(c) 12 hours

(d) 48 hours

31. A geostationary satellite is orbiting the earth at a height of 6R above the surface of the earth, R being

the radius of the earth. The time period of another satellite at a height of 2.5 R from the surface of earth

is

(a) 6 hr

(b) 6 hr

(c) 5 hr

(d) 10 hr

32. The distance of Neptune and Saturn from the sun are nearly 1013 m and 1012 m respectively.

Assuming that they move in circular orbits, their periodic times would be in the ratio of

(a) 10

(b) 100

(c) 10

(d) 1000

33. A satellite is orbiting close to the surface of the earth, then its speed is

(a)

(b) Rg

(c)

(d)

34. If the gravitational force between two objects were proportional to 1/R (and not as 1/R2) where R is

separation between them, then a particle in circular orbit under such a force would have its orbital

speed v proportional to

(a)

(b) R0

(c) R1

(d)

35. Imagine a light planet revolving around a very massive star in a circular orbit of radius R with a

period of revolution T. If the gravitational force of attraction between the planet and the star is

proportional to then

(a) T2 R2

(b) T2

(c) T2

(d) T2 R3

36. The period of a satellite in a circular orbit of radius R is T. The period of another satellite in circular

orbit of radius 4R is

(a) T/4

(b) 8T

(c) 2T

(d) T/8

37. A planet moves around the sun. At a point A, it is closest from the Sun at a distance d1 and has a

speed v1. At another point B, when it is farthest from the sun at a distance d2, its speed will be

(a)

(b)

(c)

(d)

38. The period of geostationary artificial satellite of earth is

(a) 6 hours

(b) 12 hours

(c) 24 hours

(d) 365 days

39. If r represents the radius of the orbit of a satellite of mass m moving round a planet of mass M,

the velocity of the satellite is given by

(a) v2 =

(b) v2 =

(c) v =

(d) v =

40. A missile is launched with a velocity less than the escape velocity. The sum of its kinetic and

potential energy is

(a) Positive

(b) Negative

(c) Zero

(d) may be positive or negative

41. The escape velocity of projection from the earth is approximately (R = 6400 km)

(a) 7 km/sec

(b) 112 km/sec

(c) 12.2 km/sec

(d) 1.1 km/sec

42. If the earth is 1/4th of its present distance from the sun, the duration of the year would be

(a) 1/4 of the present year

(b) 1/6 of the present year

(c) 1/8 of the present year

(d) 1/16 of the present year

43. The relation between escape velocity and orbit velocity is

(a) ve =

(b) ve = vorb

(c) ve = 2vorb

(d) ve = vorb

44. There is no atmosphere on the moon because

(a) it is closer to the earth

(b) it revolves round the earth

(c) it gets light from the sun

(d) the escape velocity of gas molecules is less than their root mean square velocity here

45. If the radius of the earth were to shrink by 1% its mass remaining the same, the acceleration due to

gravity on the earths surface would

(a) decrease by 2%

(b) remain unchanged

(c) increase by 2%

(d) will increase by 9.8%

46. Fg and Fe represents gravitational and electrostatic forces respectively, between the two electrons

situated at a distance of 10 m. The ratio Fg/Fe is of the order of

(a) 1043

(b) 1036

(c) 1043

(d) 1036

47. The value of g at a particular point is 9.8 m/ sec2 suppose the earth suddenly shrink uniformly to

half its present size without losing any mass. The value of g at the same point (assuming that the

distance of the point from the centre of the earth does not shrink) will become

(a) 9.8 m/sec2

(b) 4.9 m/sec2

(c) 19.6 m/sec2

(d) 2.45 m/sec2

48. The planet mercury is revolving in an elliptical orbit around the sun as shown in figure. The kinetic

energy of mercury will be greater at

(a) A

(b) B

(c) C

(d) D

49. The orbit velocity of an artificial satellite in a circular orbit just above the earths surface is v. For a

satellite orbiting at an altitude of half of the earths radius, the orbital velocity is

(a)

(b)

(c)

(d)

50. If the change in the value of g at the height h above the surface of the earth is the same as at a depth

x below it, then (both x and h being much smaller than the radius of the earth)

(a) x = h

(b) x = 2 h

(c) x =

(d) x = h2

Ans. 26 to 50

26. (a)

27. (c)

28. (a)

29. (b)

30. (a)

31. (a)

32. (c)

33. (c)

34. (b)

35. (b)

36. (b)

37. (a)

38. (c)

39. (c)

40. (b)

41. (c)

42. (c)

43. (a)

44. (d)

45. (c)

46. (c)

47. (a)

48. (a)

49. (c)

50. (b)

51. One end of a towel dips into a bucket full of water and other end hangs over the bucket. It is found

that after some time the towel becomes fully wet. It happens (CPMT 86)

(a) Because viscosity of eater is high

(b) Because of the capillary action of cotton threads

(c) Because of gravitational force

(d) Because of evaporation of water.

52. For tap water and clean glass, the angle of contact is

(a) 0 (b) 90

(c) 140 (d) 8

53. Water rises up to a height h1 in a capillary tube of radius r. the mass of the water lifted in the capillary

tube is M. if the radius of the capillary tube is doubled, the mass of water that will rise in the capillary

tube will be

(a) M (b) 2M

(c) (d) 4M

54. Water rises through a height h in a capillary tube of internal radius (r). if T is the S.T. of water, then

the pressure difference between the liquid level in the container and the lowest point of the concave

meniscus is

(a) (b)

(c) (d)

55. A number of small drops of mercury coalesce adiabatically to form a single drop. The temperature of

drop

(a) Increases

(b) Is infinite

(c) Remains unchanged

(d) May decrease or increase depending upon size

56. The angle of contact between a glass capillary tube of length 10 cm and a liquid is 90. If the capillary

tube is dipped vertically in the liquid, then the liquid

(a) Will rise in the tube

(b) Will get depressed in the tube

(c) Will rise up to 10 cm in the tube and will over flow

(d) Will neither rise nor fall in the tube

Answer: (d)

57. When there are no external forces, the shape of a liquid drop is determined by

(a) Surface tension of the liquid

(b) Density of liquid

(c) Viscosity of liquid

(d) Temperature of air only

58. If T is surface tension of soap solution, the amount of work done in blowing a soap bubble from

diameter D to a diameter 2D is (PMT MP 90)

(a) 2 D2 T (b) 4 D

2 T

(c) 6 D2 T (d) 8 D

2 T

59. Choose the wrong statement from the following.

(a) Small droplets of a liquid are spherical due to surface tension

(b) Oil rises through the wick due to capillarity

(c) In drinking the cold drinks through a straw, we use the phenomenon of capillarity

(d) Gum is used to stick two surfaces. In this process we use the property of Adhesion

Answer: (c)

60. If the surface of a liquid is plane, then the angle of contact of the liquid with the walls of container is

(a) Acute angle (b) Obtuse angle

(c) 90 (d) 0

61. A capillary tube when immersed vertically in a liquid records a rise of 3 cm. if the tube is immersed in

the liquid at an angle of 60 with the vertical, then length of the liquid column along the tube will be

(a) 2 cm (b) 3 cm

(c) 6 cm (d) 9 cm

62. If sap bubbles of different radii are in communication with each other (PMT MP 88, NCERT 80)

(a) Air flow from the larger bubble into the smaller one until the two bubbles are of equal size

(b) The sizes of the bubbles remain unchanged.

(c) Air flows from the smaller into the larger on and lager bubble grows at the expense of the smaller

one

(d) Air flows from the larger into the smaller one becomes equal to that of the larger one and the large

one equal to that of the smaller one.

63. A capillary tube of radius r can support a liquid of weight 6.28 10-4 N. if the surface tension of the

liquid is 5 10-2 N/m. the radius of capillary must be

(a) 2.5 103

m (b) 2.0 104

m

(c) 1.5 103

m (d) 2.0 103

m

64. The work done in blowing a soap bubble of radius R is W1 and that to a radius 3R is W2. the ratio of

work done is

(a) 1:3 (b) 3:1

(c) 1:9 (d) 9:1

65. When the angle of contact between a solid and a liquid is 90, then

(a) Cohesive force > Adhesive force

(b) Cohesive force < Adhesive force

(c) Cohesive force = Adhesive force

(d) Cohesive force >> Adhesive force

66. Rain drops are spherical in shape because of

(a) Surface tension

(b) Capillary

(c) Downward motion

(d) Acceleration due to gravity

67. A sheet can be made water proof by coating it with a substance that changes the angle of contact

(a)

(b) To zero

(c) From acute to obtuse

(d) From obtuse to acute

68. Water rises in a capillary tube to a certain height such that the upward force due to surface tension is

balanced by 75 10-4 N, forces due to the weight of the liquid. If the surface tension of water is

6 102

N/m, the inner-circumference of the capillary must be

(a) 1.25 102

m (b) 0.50 102

m

(c) 6.5 102

m (d) 12.5 102

m

69. What is the change in surface energy, when a mercury drop of radius R splits up into 1000 droplets of

radius r?

(a) 8 R2T (b) 16 R

2T

(c) 24 R2T (d) 36 R

2T

70. Which of the following is not based one the principle of capillarity

(a) Floating of wood on eater surface

(b) Ploughing of soil

(c) Rise of oil in wick of lantern

(d) Soaking of ink by bloating paper

71. The rise of a liquid in a capillary tube does not depend upon

(a) Angle of contact

(b) Density of the liquid

(c) Radius of the capillary tube

(d) Atmospheric pressure

72. The height of water in a capillary tube of radius 2 cm is 4 cm. what should be the radius of capillary,

if the water rises to 8 cm in tube? (MHT-CET-2001)

(a) 1 cm (b) 0.1 cm

(c) 2 cm (d) 4 cm

73. The work done to get n smaller equal size spherical drops from a bigger size spherical size drop of

water is proportional to (EAMCET 91)

(a) (b)

(c) (d)

74. For a liquid, which is rising in a capillary tube, the angle of contact is

(a) 90 (b) 180

(c) Acute (d) Obtuse

75. W is the work done, when a bubble of volume V is formed from a solution. How much work is

required to be done to form a bubble of volume 2V?

(a) 2 W (b) W

(c) 21/3

W (d) 41/3

W

Ans. 51 to 75

51. b

52. d

53. b

54. c

55. d

56. d

57. a

58. c

59. c

60. d

61. c

62. c

63. d

64. c

65. c

66. a

67. c

68. d

69. d

70. a

71. d

72. a

73. c

74. c

75. d