Question

A force is needed to — (i) change the state of motion or state of rest of the body (ii) keep the body in motion (iii) keep the body stationary (iv) keep the velocity of body constant

February 28, 2024

Answer

(i) change the state of motion or state of rest of the body

Reason — According to Newton’s first law of motion, if a body is in a state of rest, it will remain in the state of rest and if it is in the state of motion, it will remain moving in the same direction with the same speed unless an external force is applied on it.

Hence, to change the state of motion or state of rest, external force is required.

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