A ceiling fan is turned on and reaches an angular speed of 60 rev/min in 20 s.It is then turned off and coasts to a stop in 40 s.In the one minute of rotation,through how many revolutions did the fan turn?
A) 30
B) 60
C) 0
D) 600

Question

Quizplus · Accepted Answer

The fan accelerates to 60 rev/min in 20 s, which is 1/3 of a minute. The average speed during this time is 30 rev/min, so it completes 10 revolutions. After being turned off, it coasts to a stop in 40 s (2/3 of a minute) with an average speed of 30 rev/min, completing 20 revolutions. Total revolutions = 10 + 20 = 30.

A Ceiling Fan Is Turned on and Reaches an Angular