### Mechanics

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

[M^{0}L^{0}t^{0}]

[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/s^{2}

2 m/s^{2}

5 m/s^{2}

0.5 m/s^{2}

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^{-7}N

1.01 x 10^{-8}N

1.6 x 10^{-9}N

1.6 x 10 ^{-8}

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

0°

45°

90°

120°

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

friction of air

tension on thread

gravity

mass

54. Powder cling to skin because of **[2074]**

compression

cohesion

adhesion

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

(8^{2} + 6^{2})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 = $\overrightarrow{\mathrm{2i}}+\overrightarrow{\mathrm{3j}}-\overrightarrow{\mathrm{4k}}$ newton acts on a body. In 5 seconds the force displaces the body through a displacement S = $\overrightarrow{\mathrm{3i}}+\overrightarrow{j}-\overrightarrow{\mathrm{2k}}$ 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]**

[M^{1}L^{0}T^{-2}]

[M^{1}L^{1}t^{-1}]

[M^{0}L^{1}T^{-2}]

[M^{2}L^{0}T^{-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

r^{2}

56. A constant torque acting on a uniform circular wheel changes its angular momentum from L_{0} to 4L_{0} in 4 second. The magnitude of this torque is **[2072]**

(3/4)L_{o}

L_{o}

4_{o}

12L_{o}

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 10^{11}m 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 $\overrightarrow{L}$

Perpendicular to $\overrightarrow{L}$

Always zero

180° $\overrightarrow{L}$

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/s^{2} is given by**[2071]**

7.348 cm

0.918 cm

3.674 cm

1.837 cm