Question

What is the difference between non-uniform circular motion and uniform circular motion? Give examples.

Answer 1

In physics, circular motion is defined as the movement of an object along the circumference of a circle or rotation along a circular path. The circular motion can be uniform if the angular rate of rotation and speed are constant. The motion can be non-uniform if the angular rate of rotation is varying with time. An electron moving perpendicular to the magnetic field is an example of circular motion.

Complete solution step-by-step:

Non-uniform Circular motion	Uniform Circular motion
Non-uniform circular motion implies the movement of an object along a circular path with variable speed.	Uniform circular motion implies the movement of an object along a circular path with constant speed.
Angular and tangential acceleration are non-zero.	Angular and tangential acceleration are zero.
Linear speed and angular speed of the particle vary with time.	Linear speed and angular velocity of the particle remains constant.
Kinetic energy of the particle varies with time.	Kinetic energy of the particle remains constant.
The net linear acceleration of the particle is not radial.	The net linear acceleration of the particle is radially inwards.
The magnitude of centripetal force is not constant.	The magnitude of centripetal force is constant.
The magnitude of centripetal acceleration in a non-uniform circular motion is not constant.	The magnitude of centripetal acceleration in a uniform circular motion is constant.
Example: Motion of a body on vertical circle, vertical circle with a string and bob, roller coaster, etc.	Example: Motion of the Earth around the Sun, second, minute and hour hands of watch, motion of cyclists on a circular track etc.

Note:
If the students have clear knowledge of uniform and non -uniform motion and circular motion, then they can use that information to differentiate between uniform circular motion and non-uniform circular motion. Students must remember that the uniform circular motion is accelerated because the velocity changes due to continuous change in direction of the motion.