Angular Motion Flashcards
What is angular motion?
Movement of a body or part of a body in a circular path about an axis of rotation
What does angular motion result from?
An eccentric force applied to a body
What is an eccentric force?
A force applied outside the centre of mass, resulting in angular motion. An eccentric force is also known as torque (a turning or rotational force)
Where does the longitudinal axis run?
The longitudinal axis runs from head to toe through the centre of mass
- e.g. pirouette
Where does the transverse axis run?
The transverse axis runs from left to right through the centre of mass
- e.g. somersaults
Where does the frontal axis run?
The frontal axis runs from from to back through the centre of mass
- e.g. cartwheel
What are the 3 descriptors which are important to angular motion?
- Angular velocity
- Moment on inertia
- Angular momentum
What is angular velocity and how can it be calculated?
Angular velocity is the rate of change in angular displacement or the rate of rotation.
Angular velocity = angular displacement / time taken
What is moment of inertia and how is it calculated?
Moment of inertia is the resistance of a body to change its state of angular motion or rotation.
Moment of inertia = sum of (mass x distribution of mass from axis)
What are the 2 factors that affect moment of inertia?
- Mass (the greater the mass, the greater the moment of inertia)
- Distribution of mass from axis (the further the mass moves, the greater the MoI)
What is angular momentum and how is it caluculated?
Angular momentum is the quantity of angular motion possessed by a body.
Angular momentum = moment of inertia x angular velocity````
What is meant by the term ‘Conservation of Angular Momentum’?
Angular momentum is a conserved quantity which remains constant unless an externa eccentric force or torque is applied. As moment of inertia increases, angular velocity will decrease and vice versa.
