Circular Motion Flashcards
Angular displacement
The angle through which an object moves in a given time
Measured in radians
Angular displacement formula
s=rθ
Angular displacement for a full circle
2π radians
Radians to degrees and vice versa
Shift
Set up
2
Linear velocity
Rate of change of linear displacement
Measured in meters/second
For an object in circular motion, its linear velocity is what
Tangential to the objects circular path
Constantly changing as the object moves around in a circle
Angular velocity equation
w=△θ/△t
Angular velocity
Rate of change of angular displacement
Measured in radians/second
rpm
Revs per minute
How many revolutions completed in a minute
rms(revs^-1)=Frequency=rpm/60
revs^-1 into rads^-1
x2π
Angular velocity given frequency
2πf
Angular velocity given time period
2π/T
Linear velocity given frequency
2πrf
Linear velocity given time period
2πr/T
Frequency
Number of complete revolutions per second
Is a ball swung around someone’s head accelerating if traveling at a constant speed in a circle
Yes
Speed is constant
But velocity is constantly changing since constantly changing direction
Acceleration = Change in velocity/time
What must act on a ball to keep it moving in a circular path when swung around a head
A resultant force
Centripetal force
Always acting towards the centre of rotation
Coming from the tension