Question

when should we say an object is in motion?

Answer 1

You can describe the motionof an object by its position, speed, direction, and acceleration. An object is moving if its position relative to a fixed point is changing. Even things that appear to be at rest move.

Answer 2

$\large\mathsf{Hoy !!}$
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An object is said to be in motion when it changes its place with time and respect to its surrounding.

For example : A moving car.

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