Module 5.2 - Circular Motion

Define angular velocity and give its units

An object’s rate of change of angular position; measured in radians per second

Define centripetal acceleration

The acceleration of an object moving in circular motion

Define centripetal force

The resultant force responsible for an object moving in circular motion. It always acts towards the centre of the object’s rotation and perpendicular to the direction of motion

What is the equation for angular velocity in terms of time period and/or frequency?

ω=2πf=2π/T

What is the equation for angular velocity in terms of velocity and radius?

v=ωr; v is velocity; ω is angular velocity; r is radius

What is the equation for centripetal acceleration in terms of velocity?

a=v²/r

What is the equation for centripetal acceleration in terms of angular frequency?

a=ω²r

What is the equation for centripetal force?

F=mv²/r=mω²r

When the rate of rotation of an object in centripetal motion increases, what happens to the forces acting on it?

Centripetal forces are increased

Why does the centripetal force not affect the speed of the object in circular motion?

It acts perpendicular to the direction of motion