A ceiling fan is rotating at 0.70 rev/s. When turned off, it slows uniformly to a stop in 2.9 s.

(a) How many revolutions does it make in this time?
(b)Using the result from part (a), find the number of revolutions the fan must make for its speed to decrease from 0.7 rev/s to 0.35 rev/s.

1 answer

average speed= .35rev/s

so in 2.9 seconds, it goes...

b) well, when it is half done, 2.9/2 seconds has elapsed.

average speed= (.7+.35)/2
rev= avg speed*2.9/2 revs.