Question

Consider the following statements:
(a) No net force acts on a rain drop falling vertically with a constant speed.
(b) If net force acting on the body is zero, momentum of the body remains constant.
(c) Particle of different masses falls with different acceleration on earth.
(d) It is easier to start motion in a heavier body than a lighter body.
Which of the above statements are correct?

• A. (b) and (c)
• B. (a) and (b)
• C. (a), (b) and (d)
• D. All of the above

Answer 1

The correct option is B (a) and (b)

Rain drop is falling vertically with constant velocity, then no net force is acting on the rain drop.

Net force equals to zero implies, rate of changes of momentum is zero which means momentum is not changing with time.

Particle of different masses falls with same acceleration, which is acceleration due to gravity on earth.

To change the state (state of rest or state of motion) of a body we need external force. Force = mass x acceleration

Hence more force will be required for heavier body.