3.1 - Circular Motion

Period, T for a point describing a circle

Time taken for one complete circuit

Frequency

The number of circuits or cycles per second

The radian

A unit of measurement of angles equal to about 57.3 degrees, equivalent to the angle subtended at the centre of a circle by an arc equal in length to the radius

Convert radians to degrees

Angle x 180/\pi

Convert degrees to radians

Angle x \pi / 180

Angular velocity

Angle swept out by the radius in unit time

Equations for angular velocity

ω=angle/t

ω=2\pi f = 2\pi /T

Centripetal force

The resultant force acting on a body moving at constant speed in a circle. Directed towards the centre of the circular motion

Centripetal acceleration

An acceleration that applies to motion on a circular path. Directed towards centre of the circle

Direction centripetal acceleration and force are directed

Centre of the circle

Explain what continuous change in direction implies during circular motion

Change of velocity and acceleration

Tension from the bottom of a circle

T = F + W

Tension from the top of a circle

T = W - F

Requirement for vertical circular motion to occur

Centripetal Acceleration is greater than or equal to acceleration due to gravity

Relationship between T and f

T = 1/f

f = 1/T