4.2 Angular Motion Flashcards
Angular motion
Movement around a fixed point
Torque
The rotational consequence of a force
Newtons first law of angular motion
A rotating body will continue to turn about its axis of rotation with constant angular momentum unless an external rotational force (torque)
Newtons second law of angular motion
The rate of angular momentum of a body is proportional to the force (torque) acts
Newtons 3rd law of angular motion
When a force (torque) is applied by one body to another, the second body will exert an equal and opposite force (torque) on the body
Radian
Unit of measurement for angles
1 radian = 57.3 degrees
Angular displacement
The smallest change in angle between the start and finish point of a rotation
Angular velocity
The rate of change of angular displacement
Angular velocity (rad/s) = angular displacement (rad) divided by time (s)
Can be increased by bringing arms/legs closer to axis of rotation
Angular acceleration
The rate of change of angular velocity
Angular velocity = (rad/s2)= change in angular velocity (rad/s) divided by time (s)
Moment of Inertia
A body’s resistance to angular motion (rotation)
The greater the mass, the greater the resistance to change and therefore the greater moment of inertia
Angular Momentum
The quantity of rotation a body possesses or more simply, spin