Question

A flywheel turns through 46 rev as it slows from an angular speed of 3.1 rad/s to a stop.

Assuming a constant angular acceleration, find the time for it to come to rest?

What is its angular acceleration (in rad/s^2) ?

How much time is required for it to complete the first 23 of the 46 revolutions?

Answer 1

The average angular speed will be 1.55 rad/s.
(average speed)*(stopping Time) = 2 pi * 46 radians
Time(s) = (92 pi rad)/(1.55 rad/s) = 186.5 s

Angular acceleration = -(Initial angular speed)/(Time to stop)

Derive an equation for # of turns (n) vs t and use it to solve for t when n=23.

Answer 2

15