1

In order to remove the error of parallax when talking measurements with a metre rule, the eye should be focused

A

slantingly towards the right on the markings

B

slantingly towards the left on the markings

C

vertically downwards on the markings

D

vertically upwards on the markings

CORRECT OPTION:
c

2

A load is pulled at a uniform speed along a horizontal floor by a rope at 45^{o} to floor. If the force in the rope is 1500N, what is the frictional force on the load ?

A

1524N

B

1350N

C

1260N

D

1061N

CORRECT OPTION:
d

F = mg cos 45^{o} = 1500 x 0.708

3

Calculate the total distance covered by a train before coming to rest if its initial speed is 30ms^{-1} with a constant retardation of 0.1m^{-2}

A

5500m

B

4500m

C

4200m

D

3000m

CORRECT OPTION:
b

S = \(\frac{V^2 - U^2}{20}\)

S = \(\frac{0^2 - 30^2}{2 \times 0.1}\)

S = \(\frac{0^2 - 30^2}{2 \times 0.1}\)

4

A car starts from rest and moves with a uniform acceleration of 30ms^{-2} for 20s. Calculate the distance covered at the end of the motion

A

6km

B

12km

C

18km

D

24km

CORRECT OPTION:
a

S = \(ut + \frac{1}{2}at^2\)

S = \(0 \times 2 + \frac{1}{2} \times 30 \times 20^2\)

S = \(0 \times 2 + \frac{1}{2} \times 30 \times 20^2\)

5

A rocket is fired from the earth's surface to a distant planet. By Newton's law of universal gravitation, the force F will

A

increase as r reduces

B

increase as G varies

C

remains constant

D

increases as r increases

CORRECT OPTION:
a

6

If a freely suspended object is pulled to one side and released, it oscillates about the point of suspension because the

A

acceleration is directly proportional to the displacement

B

motion is directed away from the equilibrium point

C

acceleration is directly proportional to the square of the displacement

D

velocity is minimum at the equilibrium ponit

CORRECT OPTION:
a

7

An object moves in a circular path of radius 0.5m with a speed of 1ms^{-1} What is its angular velocity?

A

8 rads^{-1}

B

4 rads^{-1}

C

2 rads^{-1}

D

1 rads^{-1}

CORRECT OPTION:
c

W = \(\frac{v}{r} = \frac{1}{0.5}\)

8

An object of mass 20kg slides down an inclined plane at an angle of 30^{o} to the horizontal. The coefficient of static friction is?

[g = 10ms^{-2}]

[g = 10ms

A

0.2

B

0.3

C

0.5

D

0.6

CORRECT OPTION:
d

\(\mu = tan\theta = tan30\)

9

A block and tackle is used to raise a load of 250N through a vertical distance of 30m. What is the efficiency of the system if the work done against friction is 1500J?

A

62.5%

B

73.3%

C

83.3%

D

94.3%

CORRECT OPTION:
c

Y = \(\frac{work output}{work input} \times \frac{150}{1}\)

Y = \(\frac{250 \times 30}{250 \times 30 + 1500} \times \frac{150}{1}\)

Y = \(\frac{250 \times 30}{250 \times 30 + 1500} \times \frac{150}{1}\)

10

If a load of 1 kg stretches a cord by 1.2cm, what is the force constant of the cord? {g=10ms^{-2}}

A

866Nm^{-1}

B

833Nm^{-1}

C

769Nm^{-1}

D

667Nm^{-1}

CORRECT OPTION:
b

K = \(\frac{F}{e}\)

K = \(\frac{1 \times 10}{\frac{0.2}{100}}\)

K = \(\frac{10}{12} \times \frac{1000}{1}\)

K = \(\frac{1 \times 10}{\frac{0.2}{100}}\)

K = \(\frac{10}{12} \times \frac{1000}{1}\)

Pages: