Circular Motion

Uniform Circular Motion

Uniform circular motion is used to describe the motion of an object moving in a circular path. An object moving in a circle is constantly changing directions, however the tangental velocity will remain constant throughout. This idea is an essential part of uniform circular motion because it allows kinematics equations to be applied to an object moving in a circle. An object moving in a circle is also affected by an acceleration towards the center, centripetal acceleration. 

Important Equations

Non-Uniform Circular Motion

In non-uniform circular motion the net acceleration is not longer pointing towards the center. The tangental velocity is changing. When the radius of the circle remains constant, the changing velocity changes the centripetal acceleration. So not only is the tangental velocity changing, the centripetal velocity is changing too. They are proportional to each other, so when the tangental velocity increases/decreases, then the centripetal acceleration increases/decreases too. 

The red arrow is the net acceleration and the green
arrow is the magnitude of the tangental velocity.