Hi Krystle,
Angular velocity is simply the change in the angle divided by the change in time. 50 rpm is an angular velocity (revolutions per minute). Another common unit for angular velocity is radians per second.
50 revolutions is equal to 100pi radians (1 revolution is 2pi radians so 50 of them is 100pi)
1 minute is 60 seconds.
So 50 revolutions per minute is the same as 100pi radians per 60 seconds. This reduces to 5pi/3 radians per second.
Hope this helps.
:)
