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### Mechanics

51. The rate of tension and surface tension has dimension of [2075]

[M0L0t0]

[L]

[L-1]

[LT-1]

52. A force of 5N acts on a body of weight 10N the acceleration of body is [2075]

50 m/s2

2 m/s2

5 m/s2

0.5 m/s2

53.The depth from surface of earth at which value of acceleration due to gravity become half of on the surface of earth is [2075]

$R$

$\sqrt{2}R$

$\frac{R}{2}$

$\frac{R}{4}$

54. Spokes in a bicycle wheel is used to[2075]

Increase mass

Give better mass

Increase moment inertia

Drive Easily

55. If length of wire is doubled keeping the diameter constant, it’s Young's modulus will [2075]

increases

decrease

remains same

depend upon nature of matter

56.A rain drop of radius 0.3mm has terminal velocity Im/s in air.The viscosity of air is 18 x 10-5 poise, then viscous force is [2075]

1.01 x 10-7N

1.01 x 10-8N

1.6 x 10-9N

1.6 x 10 -8

52. A projectile goes farthest away from Earth, when the angle of projection is [2074]

45°

90°

120°

53. A simple pendulum where set into vibration comes to neat after sometimes because of [2074]

friction of air

gravity

mass

54. Powder cling to skin because of [2074]

compression

cohesion

capillarity

55. Viscosity is inherent property of liquid and gases and is more closely related to [2074]

inertia

shearing sharing

transfer of momentum

surface tension

53. A man walks 8 m forwards East and 6m towards North. The magnitude of displacement is [2073]

14m

2m

8m

(82 + 62)m

54. If initial velocity of a projectile is doubled, the maximum range will by [2073]

2 times

4 times

8 times

16 times

55. Which of the following friction is maximum?

rolling

Kinetic

rolling + kinetic

static

56. If the speed of rotation of earth increases, the weight of the body earth’s surface becomes [2073]

smaller

zero

greater

unaffected

57. A weightless rubber balloon has 100g of water in it. Its weight in water will be[2073]

100g

50g

> 100g

zero

51. A force F = $\stackrel{\to }{\mathrm{2i}}+\stackrel{\to }{\mathrm{3j}}-\stackrel{\to }{\mathrm{4k}}$ newton acts on a body. In 5 seconds the force displaces the body through a displacement S = $\stackrel{\to }{\mathrm{3i}}+\stackrel{\to }{j}-\stackrel{\to }{\mathrm{2k}}$ meter. The power (in watt) of the force is [2072]

4.3

3.4

5.4

6.3

52. Two simple harmonic waves are represented respectively by y1 = A1 sin ωt and y2 = A2 cos ωt. The phase difference between the two wave is [2072]

3π / 2

π

π/2

π/4

53. A river is flowing west to east at a speed of 5 m/min. A man on the south bank of the river, capable of swimming at 10m/min in still water, wants to swim across the river by the shortest path. He should swim in the direction [2072]

due north

30° East of North

60° East of North

30° West of North

54. Dimension of surface energy is [2072]

[M1L0T-2]

[M1L1t-1]

[M0L1T-2]

[M2L0T-2]

55. The terminal velocity of a small sized spherical body of radius r falling vertically in a viscous liquid is given as one of the following proportionality with radius. [2072]

r-2

r-1

r

r2

56. A constant torque acting on a uniform circular wheel changes its angular momentum from L0 to 4L0 in 4 second. The magnitude of this torque is [2072]

(3/4)Lo

Lo

4o

12Lo

51. The dimension of (h/e) are same as that of [2071]

Magnetic field

Electric field

Magnetic flux

Electric flux

52. The number of significant figure in 0.0030 x 1011m are [2071]

5

4

11

2

53. μk and μk are coefficent of static and kinetic friction between two bodies. Then [2071]

μs ≥ μk

μs < μk

μs = 0 and μk > 0

μk < 0 and μk <0

54. When a torque acts on a body, the change in the angular momentum of the body is [2071]

Perpendicular to $\stackrel{\to }{L}$

Perpendicular to $\stackrel{\to }{L}$

Always zero

180° $\stackrel{\to }{L}$

55. The Poisson's ratio of material can't be [2071]

0.10

0.20

0.40

0.65

56. The depth of water at which air bubble of radius 0.4mm may remain in equilibrium (surface tension of water = 72 x 10-3 N/m, g = 9.8 m/s2 is given by[2071]

7.348 cm

0.918 cm

3.674 cm

1.837 cm

I there is