The diameter of each wheel of a bicycle is 27 inches. If you are traveling at a speed of 10 miles per hour on this​ bicycle, through how many revolutions per minute are the wheels​ turning?

1 Answer
Jan 30, 2018

#RPM~=124.5#

Explanation:

.

The perimeter (circumference) of the wheel is:

#P=2pir=pid=pi(27)=27pi# in

This is also the distance the bicycle travels with each revolution of the wheel.

To figure out the number of revolutions of the wheel over a distance of #10# miles, we convert the #10# miles to inches and divide it by #P#:

#1# mile #=63360# inches

#10(63360)=633600# inches

#RPH=633600/(27pi)# (this is the number of revolutions in one hour)

We divide this by #60# to get the number of revolutions per minutes or #RPM#:

#RPM=(633600/(27pi))/60=(633600/(27pi))(1/60)=10560/(27pi)=10560/84.823=124.49#