Answer:
Ф=1716.8 Rev
Step-by-step explanation:
A machinist turns the power on to a grinding wheel, at rest, at time t = 0 s. The wheel accelerates uniformly for 10 s and reaches the operating angular velocity of 58 rad/s. The wheel is run at that angular velocity for 30 s and then power is shut off. The wheel slows down uniformly at 1.4 rad/s2 until the wheel stops. In this situation, the total number of revolutions made by the wheel is closest to:
the time it takes to stop revolution will be found using this using this equation
ω2=final angular velocity
ω1=initial angular velocity
∝=angular deceleration
t=time
ω2=ω1+∝t
0=58 rad/s-1.4 rad/s^2t
t=58/1.4
t=39.28secs
to get the total number of revolution made by the wheel ,we get the area under the graph, which is a trapezium
Ф=1/2(20+39.2)*58
Ф=1716.8 Rev