4.2 Angular Motion

Question 1

Angular motion

Answer 1

Movement around a fixed point

Question 2

Torque

Answer 2

The rotational consequence of a force

Question 3

Newtons first law of angular motion

Answer 3

A rotating body will continue to turn about its axis of rotation with constant angular momentum unless an external rotational force (torque) is exerted upon it

Question 4

Newtons second law of angular motion

Answer 4

The rate of angular momentum of a body is proportional to the force (torque) causing it and the change that takes place in the direction in which the force (torque) acts

Question 5

Newtons 3rd law of angular motion

Answer 5

When a force (torque) is applied by one body to another, the second body will exert an equal and opposite force (torque) on the other body

Question 6

Radian

Answer 6

Unit of measurement for angles

1 radian = 57.3 degrees

Question 7

Angular displacement

Answer 7

The smallest change in angle between the start and finish point of a rotation

Question 8

Angular velocity

Answer 8

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

Question 9

Angular acceleration

Answer 9

The rate of change of angular velocity

Angular acceleration = (rad/s2)= change in angular velocity (rad/s) divided by time (s)

Question 10

Moment of Inertia

Answer 10

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

Question 11

Angular Momentum

Answer 11

The quantity of rotation a body possesses or more simply, spin