Question

Motion and rest are relative. How do you justify this?

Answer 1

Motion:

An object is said to be in motion as long as its position changes with respect to its surrounding.

Rest:

An object is said to be at rest if its position does not change with respect to its surrounding.

Motion and rest are relative:

1. Consider two persons in a lift.
2. Assume the lift is moving upwards.
3. The two persons inside the lift are not in motion with respect to each other and the lift.
4. But for the person outside the lift, the two persons are in motion and moving upwards.

Hence, motion and rest are relative.