Question

What is uniform circular motion? Establish a relationship between linear and angular velocity.

What do you mean by ‘average velocity’? How it is calculated?

Answer 1

unchanged circular motion with respect to time is called uniform circular motion.average velocity is the rate of change in displacement.
velocity = displacement/time.

Answer 2

When a travels equal distances in equal interval of time on a circular path the motion is called uniform circular motion.
The relationship between linear speed and angular velocity is
Linear speed=Angular velocity*Radius
$v = wr$
When the sum of initial velocity and final velocity is divided by 2 it is called average velocity.
$\frac{initial \: velocity + final \: velocity}{2}$