Non-Uniform Circular Motion

Do you see your racing car changing speeds at the U-turns? Or have you watched the ball moving at a different speed when you throw it? All these kinds of motions are classified as circular motions. There are two types of circular motions: uniform circular motion and non-uniform circular motion. 

What is non-uniform circular motion?

Non-uniform circular motion is a kind of circular motion in which the object travels in a circular trajectory path. However, the speed it travels remains fluctuating and is not constant. This is the crudest non-uniform circular motion meaning. 

In a non-uniform circular motion, the distance between two objects in a circular path may change too. The velocity of the object travelling in circular motion has variations with time when it is non-uniform. 

Non-uniform speed

When an object completes a varied distance in a constant interval of time, it is known as non-uniform speed. That is, the time for the object to cover the circular path would be the same. However, when the object covers an unequal distance, it is said to have completed non-uniform speed. 

Non-uniform velocity

Velocity refers to the speed at which the object travels in a particular direction. When an object is travelling at an unequal speed in a circular motion, the velocity is also unequal or non-uniform. Here, the time intervals will vary because the object would be travelling at an unequal speed or velocity. 

Non-uniform acceleration

Acceleration is defined as the rate at which velocity fluctuates with respect to speed and direction. In a uniform motion, acceleration is the changed velocity in constant intervals of time. But, when an object is changing at varying speeds at unequal intervals of time, it is non-uniform acceleration. For a non-uniform circular motion, the acceleration is the uneven change in speed in differentiated intervals.

Features of non-uniform circular motion

There are some distinctive features of non-circular motion. These are:

• The angular acceleration remains zero. Here, the angular acceleration is the time rate of change in velocity. 
• The tangential acceleration remains the same. Here, the tangential acceleration is the acceleration of the component that is tangent to the motion. 
• There is centripetal acceleration that determines the change in direction of the moving object. 
• The angular velocity can decrease or increase constantly. 

Non-uniform circular motion is the circular movement that witnesses a frequent change in velocity, acceleration and distance. This kind of circular motion can be understood practically with some common examples of non-uniform circular motion.

Examples of non-uniform circular motion

Here are some day to day examples of non-uniform circular motion:

Example 1

Consider a ball being thrown at you. A ball is a circular object and hence travels in a circular motion, even if thrown straight. The speed that the ball is travelling is unequal due to non-uniform circular motion. The velocity is varied for the ball. As it is thrown at you, the velocity is decreased. But, when it moves farther, the velocity is increased. The acceleration over here is different. The ball travels in unequal time intervals and speed. 

Example 2

Suppose you are stuck with your vehicle in a traffic jam on a circular road. Here, your car will experience a non-uniform circular motion. The car has to be at rest and then move at different velocities. If there is ample space between, the car would drive at a slightly increased speed. In a vice-versa situation, it will move at a decreased velocity. Also, the acceleration will fluctuate because the time intervals of moving the car would be different. 

Example 3

Consider playing with a top. As you begin spinning the top, it moves in a circular motion. At first, the speed and velocity of the top are increased and it covers more distance. However, the velocity and speed decrease over a while. Here, it is a non-uniform circular motion. This is because the speed, velocity as well as acceleration keeps changing.

Difference between uniform and non-uniform circular motion

Conclusion

There are two types of circular motions- uniform circular motion and non-uniform circular motion. We often encounter non-uniform circular motion as part of our day to day life. Understanding the non-uniform circular motion meaning along with some examples of non-uniform circular motion is crucial for understanding this crucial concept of physics.