Circular Motion Flashcards
Angular displacement
The change in angle, in radians, of a body as it rotates around a circle
Radian
The angle subtended at the centre of a circle by an arc equal in length to the radius of the circle
Frequency
The number of complete oscillations per unit time
Period
The time taken for one complete oscillation, in seconds
Linear Speed around circle
2(pi)(radius)/period
Angular displacement
The change in angle, in radians, of a body as it rotates around a circle
Why is an object travelling in uniform circular motion accelerating while speed is constant?
The velocity is constantly changing direction and is therefore accelerating
Angular speed
The rate of change in angular displacement with respect to time
Angular speed, scalar or vector?
Scalar
What provides the force to an object that is travelling in uniform circular motion when the object is attached to a string
The stretched string applies a force to the object pulling it so that is moves in a circle of radius r around a fixed point
Key points about centripetal force:
-Perpendicular to the direction of motion along with acceleration
-Acts towards the centre of the circle
-Not a separate force of its own
Centripetal force definition
The resultant force towards the centre of the circle required to keep a body in uniform circular motion. It is always directed towards the centre of the body’s rotation.
Linear velocity definition
The velocity of an object rotating in uniform circular motion, with respect to a linear displacement, as opposed to angular displacement
Centripetal acceleration definition
The acceleration of an object towards the centre of a circle when an object is in motion (rotating) around a circle at a constant speed
