5.1+5.2 Rotational Kinematics + Dynamics

Rigid Object

An object with a definite shape that doesn't change, so that the particles composing it stay in fixed positions relative to another.

Axis of Rotation

An imaginary line around which rotation occurs.

Angular Position

The position, , of an object according to a co-ordinate system measured in s of the angle of the object from a certain origin axis. Conventionally, this origin axis is the positive x-axis.

Radian

The angle subtended by an arc who's length is equal to the radius.

Average Angular Velocity

rate of change of angular position, rad/s

Angular Displacement

The change in angular position or the radian measure of the angle through which the body turns.

Period

In physics, the time that it takes a complete cycle or wave oscillation or for an object to make a complete circle.

Frequency

Number of complete cycles in a given time.

Constant Angular Acceleration

When an object traveling in a circular motion changes its angular velocity at a steady rate.

Torque

Force that causes rotation that is perpendicular to the distance the force is from the axis of rotation.

translational position to angular position

x = θ r

translational velocity to angular velocity

v = ω r

translational acceleration to angular acceleration

a = α r

centripetal acceleration and angular speed

a(sub)c = ω²r