Question

What is Meant by a Body in Motion? Or, What do You Mean by  a Body in Motion?

Answer 1

A body in motion may be defined as follows :

A body is said to be in motion if it change its position continuously with respect to a fixed point in Its surroundings.

Or,

If the position of a body changes with time relative to any fixed point in its surroundings, then the body is said to be at motion.

Example -

1. Cars and buses running on the road.
2. Birds and aeroplane flying in the air.
3. The running blades of a fan.
4. The different parts of a running machine.