Question

define the following and write their Si units

Answer 1

Speed:Distance travelled per unit time is Called speed. It is scalar quantity and S.I. unit is meter / second.

Velocity: Distance travelled per unit time in a given direction is called velocity of a body.
It is vector quantity and S.I unit is m/ s.

The value of velocity may be positive , negative or 0.

Acceleration: The rate of change of velocity is called acceleration .
It is vector quantity and its S.I unit ism/ s^2.