A Level Physics Practice Test: Circular Motion in Physics — Flashcards

Circular motion is when an object moves along the circumference of a circle or rotates along a circular arc. It has a constant radius, a continuous change in velocity direction, and a uniform speed. The object continuously changes direction while maintaining a constant distance from a central point. 

Circular motion can be uniform, with a constant rate of rotation and constant tangential speed, or non-uniform with a changing rate of rotation. In uniform circular motion, the particle in circular path moves with a uniform speed and covers equal distances in equal intervals of time. 

Examples of circular motion include:
Carousels or merry-go-rounds in parks
A car going around a roundabout
The moon orbiting around the Earth
The Earth revolving around the Sun
A rotating ceiling fan
A moving car's wheel
The blades in a windmill
Gears in gas turbines 

Here are some other terms related to circular motion:
Centripetal acceleration: The acceleration a particle must have to follow a circular path. It always points toward the center of rotation and has magnitude aC=v2/r.
Centripetal force: The force that causes centripetal acceleration.
Angular velocity: An axial vector with dimensions (T-1) and SI unit rad/s.