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(Code H015/PHY/03)

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S.T.-3 Paper Code: H015/PHY/03 Answer Sheet Code: 03 Time : 2.30 Hrs. Max. Marks :300

Sub: Physics Date:…………………

TO BE COMPLETED BY THE CANDIDATE

Name ..……………………………………………..…………………….………………….…….

SID. No …………………………………Signature of the candidate……..…….……..…………

DIRECTION TO CANDIDATES

1. Attempt all questions.

2. There are 75 questions. Each question carry +4 & −1 marks.

3. All questions are Multiple Choice Question (carrying only one option is correct), darken the

corresponding answer on OMR sheet provided separately.

4. Do not write any thing on answer sheet other than information asked.

5. Blank papers, clipboard. Log tables slide rules, calculators, cellular phones, pagers, and electronic

gadgets in any form are not allowed to be carried inside the examination hall.

6. Use black and blue ball point pen only in examination hall.

7. First of all fulfill the formalities in answer sheet and question paper properly before commencement.

Examination Superintendent Signature of Guardian

(Seal & Signature)

(Code H015/PHY/03)


1. The unit of atomic mass is :

(a) O=16.0000 (b) O16=16.0000

(c) C=12.0000 (d) C12=12.0000

2. The dimensional formula for coefficient of

thermal conductivity is :

(a) [MLTK] (b) [MLT−2]

(c) [MLTK−1] (d) [MLT−3K−1]

3. A hypothetical experiment conducted to

determine Young’s formula Y= cos θ Tx .τ

l3 . If

Y=Young’s modulus, T= time period, τ= torque

and l= length, then find the value of x.

(a) zero (b) 1

(c) 2 (d) 3

4. The SI unit of electron mobility is :

(a) m2s−1 V−1 (b) msV−1

(c) ms−1V (d) m2s−2 V−2

5. The density of a material in CGS system of

units is 4g/cm3.In a system of units in which

unit of length is 10 cm and unit of mass is

100g, the value of the density of material will

be :

(a) 0.04 (b) 0.4

(c) 40 (d) 400

6. The number of significant figures in the

numbers 4.8000 ×104 and 48000.50 are

respectively :

(a) 5 and 6 (b) 5 and 7

(c) 2 and 7 (d) 2 and 6

7. In an experiment four quantities a, b, c and d

are measured with percentage errors 1 %, 2%,

3% and 4% respectively. Quantity P is

calculated as follows:

P= a3b2

cd

% error in P is :

(a) 4% (b) 14%

(c) 10% (d) 7%

8. A and B are two vectors and θ is the angle

between them, if A × B = 3 A . B the value

of θ is :

(a) 900 (b) 600

(c) 450 (d) 300

9. The vector sum of two forces is perpendicular

to their vector difference. In that case, the

forces :

(a) are equal to each other

(b) are equal to each other in magnitude

(c) are not equal to each other in magnitude

(d) cannot be predicted

10. Magnitudes of four pairs of displacement

vectors are given. Which pair of displacement

vectors, under vector addition, fails to give a

resultant vector of magnitude 3 cm?

(a) 2 cm, 7 cm (b) 1 cm, 4 cm

(c) 2 cm, 3 cm (d) 2 cm, 4cm

11. The position x of a particle with respect to time

t along X-axis is given by x= 9t2−t3, where x is

in meter and t in seconds. What will be the

position of this particle when it achieves

maximum speed along +x direction?

(a) 54 m (b) 81 m

(c) 24 m (d) 32 m

12. The speed of a boat is 5 km/hr in still water. It

crosses a river of width 1 km along the shortest

possible path in 15 minutes. The velocity of

river water is :

(a) 3 km/hr (b) 4 km/hr

(c) 5 km/hr (d) 2km/hr

13. A car is moving with velocity v. If car stop after

applying break at a distance of 20 m. If

velocity of car is doubled, then how much

distance it will cover (travel) after applying

break:

(a) 40 m (b) 80 m

(c) 160 m (d) 320 m

(Code H015/PHY/03)


14. A particle starting from the origin (0,0) moves

in a straight line in the X, Y-Plane. Its co-

ordinates at a later time are ( 3 ,3). The path

of the particle makes with the X- axis an angle

of :

(a) 00 (b) 300

(c) 450 (d) 600

15. A particle moves in a straight line with a

constant acceleration. It changes its velocity

from 10 ms−1 to 20 ms−1 while passing through

a distance 13.5 m in t second. The value of t is

(in s) :

(a) 12 (b) 9

(c) 10 (d) 1.8

16. Two bodies, A (of mass 1 kg ) and B (of mass

3 Kg), are dropped from heights of 16 m and

25 m respectively. The ratio of the time taken

by them to reach the ground is :

(a) 5

4 (b)

12

5

(c) 5

12 (d)

4

5

17. A body is projected at such angle that the

horizontal range is three times the greatest

height. The angle of projection is :

(a) 3307’ (b) 4208’

(c) 5307’ (d) 2508’

18. A boy is hanging from a horizontal branch of a

tree. The tension in the arms will be maximum

when the angle between the arms is :

(a) 00 (b) 600

(c) 900 (d) 1200

19. When a spring is subjected to 4N force its

length is a meter and if 5 N is applied length is

b meter. If 9 N is applied its length is :

(a) 4b− 3a (b) 5b−a

(c) 5b−4a (d) 5b−2a

20. The mass of a lift is 2000 kg. When the

tension in the supporting cable is 28000N, then

its acceleration is :

(a) 14 ms−2 upwards (b) 30 ms−2downwards

(c) 4 ms−2 upwards (d) 4 ms−2 downwards

21. A cricketer catches a ball of mass 150 gm in

0.1 second moving with speed 20 ms−1, then

he experience force of :

(a) 300 N (b) 30 N

(c) 3 N (d) 0.3 N

22. A lineman of mass 60 kg is holding a vertical

pole. The coefficient of static friction between

his hands and the pole is 0.5. If he is able to

climb up the pole, what is the minimum force

with which he should press the pole with his

hands? (g= 10 m/s2)

(a) 1200 N (b) 600 N

(c) 300 N (d) 150 N

23. An object of mass 6 kg is moved with uniform

speed of 8 m/s for 8 sec on a surface.

Coefficient of friction between the body and the

surface is 0.6, work done for the given motion

of the body is : (take g= 10 m/s2)

(a) 2212 J (b) 2304 J

(c) 1192 J (d) 3222 J

24. 250 N force is required to raise 75 kg mass

from a pulley. If rope is pulled 12 m then the

load is lifted to 3m, the efficient of pulley

system will be

(a) 25% (b) 33.3%

(c) 75% (d) 90%

25. A body of mass 2 kg is projected at 20 m/s at

an angle 600 above the horizontal. Power due

to the gravitational force on the block at its

highest point is : (take g= 10 m/s2)

(a) 200 watt (b) 120 watt

(c) 180 watt (d) zero

26. If F = 60i + 15j − 3k N and v = 2i − 4j + 5k

m/s, then instantaneous power is :

(a) 195 W (b) 45 W

(c) 75 W (d) 100W

(Code H015/PHY/03)


27. The total energy of an electron is 3.555 MeV.

Its kinetic energy is :

(a) 3.545 MeV (b) 3.045 MeV

(c) 3.5 MeV (d) None of these

28. A spacemen in training is rotated in a seat at

the end of a horizontal arm of length 5m. If he

can withstand acceleration upto 9g, then what

is the maximum number of revolutions per

second permissible? (Take g = 10 m/s2)

(a) 13.5 rev/s (b) 1.35 rev/s

(c) 0.675 rev/s (d) 6.75 rev/s

29. A car of mass 1000 kg negotiates a banked

curve of radius 90 m on a frictionless road. If

the banking angle is 450, the speed of the car

is :

(a) 5 m/s (b) 10 m/s

(c) 20 m/s (d) 30 m/s

30. The string of a simple pendulum is horizontal.

Now it is released. The tension in the string in

the lowest position is :

(a) 2m g (b) 6 mg

(c) 3 mg (d) 4 mg

31. When a simple pendulum is rotated in a

vertical plane with constant angular velocity,

centripetal force is :

(a) maximum at highest point

(b) maximum at lowest point

(c) same at all point

(d) zero

32. A particle of mass M is moving in a horizontal

circle of radius R with uniform speed V. When

it moves from one point to a diametrically

opposite point is :

(a) Momentum does not change

(b) momentum changes by 2 MV

(c) KE changes by MV2

(d) KE changes by (1/4) MV2

33. A shell of mass 20 kg at rest explodes into two

fragments whose masses are in the ratio 2 : 3.

The smaller fragment moves with a velocity of

6 ms−1. The kinetic energy of the larger

fragment is

(a) 96 J (b) 216 J

(c) 144 J (d) 360 J

34. A shell of mass 200 g is ejected from a gun

of mass 4 kg by an explosion that generates

1.05 kJ of energy. The initial velocity of the

shell is :

(a) 40 m/s (b) 120 m/s

(c) 100 m/s (d) 80 m/s

35. Two perfectly elastic particles A and B of equal

masses travelling along the line joining them

with velocity 15 m/s and 10 m/s respectively

collide. Their velocities after the elastic collision

will be (in m/s ) respectively :

(a) 0 and 25 (b) 5 and 20

(c) 10 and 15 (d) 20 and 5

36. Three identical rods, each of length x, are

joined to form a rigid equilateral triangle. Its

radius of gyration about an axis passing

through a corner and perpendicular to the

triangle is :

(a) x

3 (b)

x

2

(c) 3

2x (d)

x

2

37. Moment of inertia of ring about its diameter is

I. Then moment of inertia about an axis

passing through centre perpendicular to its

plane is :

(a) 2 I (b) I

2

(c) 3

2 I (d) I

38. The momentum of inertia of a rod about an

axis through its centre and perpendicular to it

is 1

12 ML2 (Where M is the mass and L is the

length of the rod). The rod is bent in the middle

so that the two halfs make an angle of 600. The

(Code H015/PHY/03)


moment of inertia of the bent rod about the

same axis would be :

(a) 1

48 ML2 (b)

1

12 ML2

(c) 1

24 ML2 (d)

ML3

8 3

39. A circular disc is to be made using iron and

aluminium so that it acquired maximum

moment of inertia about geometrical axis. It is

possible with:

(a) aluminium at interior and iron surround

to it

(b) iron at interior and aluminium surround to

it

(c) using iron and aluminium layers in

alternate order

(d) sheet of iron is used at both external

surface and aluminium sheet as internal

layers

40. Moment of inertia of a uniform cylindrical wire

about its geometrical axis is :

(a) MR2 (b) 1

2 MR2

(c) 2

5 MR2 (d)

1

4 MR2

41. From a circular disc of radius R and mass 9

M, a small disc of mass M and radius R

3 is

removed concentrically. The moment of inertia

of the remaining disc about an axis

perpendicular to the plane of the disc and

passing through its centre is :

(a) MR2 (b) 4MR2

(c) 4

9 MR2 (d)

40

9 MR2

42. The speed of a homogeneous solid sphere

after rolling down an inclined plane of vertical

height h, from rest, without sliding is :

(a) gh (b) g

5 gh

(c) 4

3 gh (d)

10

7 gh

43. A body is rotating with angular velocity 30

rad/s. If its kinetic energy is 360 J, then its

moment of inertia is :

(a) 0.8 kg m2 (b) 0.4 kg m2

(c) 1 kg m2 (d) 1.2 kg m2

44. For a hollow cylinder and a solid cylinder

rolling without slipping on an inclined plane,

then which of these reaches earlier on the

ground?

(a) Solid cylinder

(b) Hollow cylinder

(c) Both simultaneously

(d) Can’t say anthing

45. A solid cylinder of mass 3 kg rolling on a

horizontal surface with velocity 4 m/s. It

collides with a horizontal spring of force

constant 200 N/m. The maximum compression

produced in the spring will be :

(a) 0.7 m (b) 0.2 m

(c) 0.5 m (d) 0.6 m

46. Which one of the following pair of quantities

has same dimension?

(a) Force and work done

(b) Momentum and impulse

(c) Pressure and force

(d) Surface tension and stress

47. A spectrometer gives the following reading

when used to measure the angle of a prism.

Main scale reading =58.5 degree

Vernier scale reading = 0.9 divisions

Given that 1 divisions on main scale

corresponds to 0.5 degree. Total divisions on

the vernier scale is 30 and match with 29

divisions of the main scale. The angle of the

prism from the above data is :

(a) 58.590 (b) 58.770

(c) 58.650 (d) 590

48. The energy (E), angular momentum (L) and

universal gravitational constant (G) are chosen

as fundamental quantities. The dimensions of

universal gravitational constant in the

dimensional formula of Planck’s constant (h) is

:

(a) 0 (b) −1

(Code H015/PHY/03)


(c) 5/3 (d) 1

49. A and B are two vectors given by A =2 i +3j and

B = i + j .The magnitude of the component of A

along B is :

(a) 5

2 (b)

3

2

(c) 7

2 (d)

1

2

50. A particle acted upon by constant forces

4i + j − 3k and 3i + j − k is displaced from the

point i + 2j − k to point 5i + 4j − 3k . Total work

done by the forces in SI unit is :

(a) 20 (b) 40

(c) 50 (d) 30

51. A particle moves in the X-Y plane under the

influence of a force such that its linear

momentum is p (t)=A [i cos(kt)−j sin (kt), where

A and k are constants. The angle between the

force and the momentum is :

(a) 00 (b) 300

(c) 450 (d) 900

52. A body moving with a uniform acceleration

crosses a distance of 65 m in the 5th second

and 105 m in 9th second. How far will it go in 20

s?

(a) 2040 m (b) 240 m

(c) 2400 m (d) 2004 m

53. An artillery piece which consistently shoots its

shells with the same muzzle speed has a

maximum range R. To hit a target which is R/2

from the gun and on the same level, the

elevation angle of the gun should be :

(a) 150 (b) 450

(c) 300 (d) 600

54. Which of the following are true?

(A) A body having constant speed can have

varying velocity

(B) Position time graphs for two objects with

zero relative velocity are parallel

(C) The numerical ratio of velocity, to

speed of an object can never

be more than one.

(a) (A) (b) (B) and (C)

(c) All (d) None of these

55. An aeroplane is flying horizontally with a

velocity of 600 km/h and at a height of 1960 m.

When it is vertically above a point A on the

ground a bomb is released from it. The bomb

strikes the ground at point B. The distance AB

is :

(a) 1200 m (b) 0.33 km

(c) 333.3 km (d) 3.33 km

56. A mass of M kg is suspended by a weightless

string. The horizontal force that is required to a

displace it unit the string makes an angle of 450

with the initial vertical direction is :

(a) Mg/ 2 (b) Mg 2 − 1

(c) Mg 2 + 1 (d) Mg 2

57. The velocity of a body of mass 20 kg

decreases from 20 m/s to 5m/s in a distance of

100m. Force on the body is :

(a) −27.5 N (b) −47.5 N

(c) −37.5 N (d) −67.5 N

58. The upper half of an inclined plane with

inclination ∅ is perfectly smooth while the

lower half is rough. A body starting from rest at

the top will again come to rest at the bottom, if

coefficient of friction for the lower half is given

by :

(a) 2 tan ∅ (b) tan∅

(c) 2 sin ∅ (d) 2 cos ∅

59. A machine gun fires a bullet of mass 40 gm

with a speed 1200 m/s. The man holding it can

exert a maximum force of 144 N on the gun.

How many bullets can he fire per second at the

most?

(a) one (b) Four

(c) Two (d) Three

60. Potential energy of a 1 kg particle free to move

along X-axis is given by

(Code H015/PHY/03)


V(x)= x4

4−

x2

2 joule

Total mechanical energy of the particle is 2

joule. Then the maximum speed in m/s is :

(a) 2 (b) 3

2

(c) 2 (d) 1

2

61. A 2 kg block slides on a horizontal floor with a

speed 4 ms/. It strikes an uncompressed spring

and compressed it till the block is motionless.

The kinetic friction is 15 N and spring constant

is 10,000 N/m. The spring compresses by :

(a) 8.5 cm (b) 5.5 cm

(c) 2.5 cm (d) 11.0 cm

62. A force of (5+3x) N acting on a body of mass

20 kg along the x-axis displaces it from x=2 to

x=6m. The work done by the force is :

(a) 20 J (b) 48 J

(c) 68 J (d) 86 J

63. The height of a waterfall is 50m. If g=9.8 ms−2,

the difference between the temperature at the

top and the bottom of the waterfall is :

(a) 1.170C (b) 2.170C

(c) 0.1170C (d) 1.430C

64. A small disc of radius 2 cm is cut from a disc of

radius 6 cm. If the distance between their

centres is 3.2 cm, what is the shift in the centre

of mass of the disc?

(a) 0.4 cm (b) 2.4 cm

(c) 1.8 cm (d) 1.2 cm

65. A ball which is at rest is dropped from a height

h metre. As it bounces off the floor its speed is

80% of what it was just before touching the

ground. The ball will then rise to nearly a height

:

(a) 0.94 h (b) 0.80 h

(c) 0.75 h (d) 0.64 h

66. A rocket of mass 6000 kg is fired from earth

with speed 1 km/s. What should be the rate of

ejection of gas, so that it moves with initial

acceleration 20 m/s2? (Take g= 10 m/s2)

(a) 60 kg/s (b) 180 kg/s

(c) 200 kg/s (d) 120 kg/s

67. A bullet of mass 10 g moving with 300 m/s hits

a block of ice of mass 5 kg and drops dead.

The velocity of ice is :

(a) 50 cm/s (b) 60 cm/s

(c) 40 cm/s (d) 30 cm/s

68. A solid sphere of mass M, radius R and having

moment of inertia about an axis passing

through the centre of mass as I, is recast into a

disc of thickness t, whose moment of inertia

about an axis passing through its edge and

perpendicular to its plane remains I. Then,

radius of the disc will be :

(a) 2R

15 (b) R

2

15

(c) 4R

15 (d)

R

4

69. A solid sphere of mass 2 kg rolls on a smooth

horizontal surface at 10 m/s. It then rolls up a

smooth inclined plane of inclination 300 with

the horizontal. The height attained by the

sphere before it stops is :

(a) 700 cm (b) 701 cm

(c) 7.1 m (d) None of these

70. A body of mass 1.5 kg rotating with larger

angular speed velocity of 0.3 rad s−1 has an

angular momentum of 1.8 kg m2s−1. The radius

of gyration of the body about an axis is :

(a) 2 m (b) 1.2 m

(c) 0.2 m (d) 1.6 m

71. A wheel has angular acceleration of 3.0 rad /s2

and an initial angular speed of 2.00 rad/s. In a

time of 2s it has rotated through an angle (in

radian) of :

(a) 6 (b) 10

(c) 12 (d) 4

72. Angular momentum of a particle rotating under

a central force is constant due to :

(a) constant torque

(Code H015/PHY/03)


(b) constant force

(c) constant linear momentum

(d) zero torque

73. Two rings of radius R and nR made up of same

material have the ratio of moment of inertia

about an axis passing through centre is 1 : 8.

The value of n is :

(a) 2 (b) 2 2

(c) 4 (d) 1

2

74. A point moves along a circle with velocity ν=at.

The total acceleration of the point at a time

when it has traced 1/8th of the circumference is

(a) ν

8a (b) 2a 4 + π2

(c) a (d) a

2 4 + π2

75. If the radius of earth contracts to half of its

present value, the length of the day will be :

(a) 48 hr (b) 24 hr

(c) 12 hr (d) 6hr

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