CBSE Class 11 Physics Laws of Motion Quiz 2

1. The mass of a body is 2 kg. It weight is

A 19.6 N B 20 N C 30 N D 40 N

2. A body is sliding down a rough inclined plane which makes an angle of 30 degree with the horizontal. If the coeffcient of friction is 0.26, the acceleration in m/s² is

A 1.95 B 2.78 C 3.47 D 4.6

3. A gun of mass 1000 kg fires a projectile of mass 1 kg with a horizontal velocity of 100 m/s. The velocity of recoil of the gun in the horizontal direction is

A 5 m/s B 0.1 m/s C 15 m/s D 20 m/s

4. A block of wood is placed on a surface. A force is applied parallel to the surface to move the body. The frictional force developed acts

A normal to the surface upwards B normal to the surface downwards C along the direction of the applied force D opposite to the direction of the applied force

5. A block of mass 2 kg rests on a rough inclined plane making an angle of 30 degree with the horizontal. The coefficient of static friction between he block and the plane is 0.7. The frictional force on the block is

A 9.8 N B 0.7 × 9.8 × √3 N C 9.8 × √3 N D 0.7 × 9.8 N

6. A particle of mass 0.3 kg is subjected to a force F = -kx with k = 15 N/m. What will be its initial acceleration if it is released from a point 20 cm away from the origin?

A 15 m/s² B 3 m/s² C 10 m/s² D 5 m/s²

7. Two bodies of masses 4 kg and 5 kg are acted upon by the same force. If the acceleration of lighter body is 2 m/s², the acceleration of heavier body is

A 1 m/s² B 1.2 m/s² C 1.6 m/s² D 1.8 m/s²

8. Out of the basic forces , gravitational force

A ranks first in strength B ranks second in strength C ranks third in strength D ranks fourth in strength

9. The frame of reference attached to a satellite of the earth is

A an inertial frame B an absolute frame at rest with respect to the stars C a non - inertial frame D a gravitational frame

10. A block of mass M is placed on a flat surface. A force is applied to move it parallel to the surface. The frictional force f developed is proportional to the

A square of the mass of the body B mass of the body C reciprocal of the mass of the body D reciprocal of the square of the body