Physics

$Average Speed=Total timeTotal distance $

It is a scalar quantity. Its unit is m/s.

It is a vector quantity and has units of m/s.

Magnitude of average velocity is always less than or equal to the average speed because displacement is always smaller than or equal to distance.

Example:

A boy covers a circle of radius $100$ m in $100$ s.

The total distance covered by him will be $d=2πr=200πm$

Average speed will be $v=td =100200π =2πm/s$

For e.g., an object thrown into air, like stone, moves at non-uniform speed, lift used to go up or down in a building.

Since velocity is a vector quantity, hence it depends on two factors namely

If any of the two will change, velocity will also get changed.

So, we can say that the object is moving with non uniform velocity, if an object is :

1. changing speed wrt time but in the same direction.

2. changing direction wrt time while moving with constant speed.( e.g., motion of a particle in a circular path with constant speed)

3. changing both speed and direction wrt time.