posted by matt on .
the tub of a clothes washer goes into its spin-dry cycle starting from rest and reaches an angular speed of 6.50 rev/s in 7.85 seconds. at this point, the person doing the laundry opens the lid, and a safety switch turns off the washer. the tub then slows to a stop in 15.07 seconds. Assuming a constant angular acceleration, while the tub is starting and stopping, how many revolutions does the tub turn during this 22.92 second interval?
oh god, could someone PLEASE help me with this question? please just don't tell me the answer, set me up with something comprehendable? any help is appreciated!!
6.50/2, times by 22.92.
Add the number of revolutions turned starting up to the number turned while slowing down. The easiest way do do this is to use the average spin rate, 3.25 rev/s (both while speeding up and while slowing down).
Total number of spins = 3.25 spins/s * (7.85 + 22.92)