Question

Ans in revs.
The tub of a washer goes into its spin-
dry cycle, starting from rest and reaching an
angular speed of 5 rev/s in 10.5 s . At this
point the person doing the laundry opens the
lid, and a safety switch turns off the washer.
The tub slows to rest in 5.6 s .
Through how many revolutions does the
tub turn? Assume constant angular accelera-
tion while it is starting and stopping. Answer
in units of rev.

Answer 1

While accelerating, the washer has an average speed of 2.5 rev/s and goes through 2.5x10.5= 26.25 revs.

While decelerating, it has the same average speed for 5.6 s, and turns 14 revs.

Add the two.

Answer 2

how did you get the 2.5 rev/s