DEVOIR 7

question1

At t = 0, a wheel rotates at rpm. A motor gives it a constant angular acceleration of 0.9 rad/s2 until it reaches 114 rpm. The motor is then disconnected. If there is no friction, how many revolutions has the wheel made at t = 21 s?

question 2

A wheel starts from rest and accelerates uniformly. It makes 43 revolutions as the frequency of rotation increases from 22 to 53 rpm. Determine: (a) the angular acceleration; (b) the number of revolutions the wheel made between the starting point and the time when its rotational frequency reached 22 rpm.