A Machinist Turns on the Power on to a Grinding

Question 32
Multiple Choice

A machinist turns on the power on to a grinding wheel at time t = 0 s.The wheel accelerates uniformly from rest for 10 s and reaches the operating angular speed of img The wheel is run at that angular velocity for 40 s and then power is shut off.The wheel slows down uniformly at img Until the wheel stops.For how long a time after the power is shut off does it take the wheel to stop? A)64 s B)62 s C)66 s D)68 s E)70 s