Motion — Science STD 9 — Question

A body is said to be in motion when its position changes continuously with respect to a stationary point taken as the reference point.

• Uniform motion: A body is said to be in uniform motion if it travels equal distances in equal intervals of time in a particular direction, no matter how small these time intervals are.

For example: A car running at a constant speed of 10m/s towards east will cover the equal distance of 10m every second towards east, so its motion will be uniform.

• Non-uniform motion: A body is said to be in non-uniform motion if it travels unequal distances in equal intervals of time.

For example: Motion of a freely falling ball from the roof of a tall building.