At a speed of 22 revolutions per minute, how long will it take a wheel of radius 10,
rolling on its edge, to travel 10 feet? (Assume p equals 22/7, and express answer to
nearest 0.1 second.)



Answer :

Well, if the radius is 10, then the circumference is [tex]\frac{2*10*22}7=\frac{440}7[/tex]
What's the unit? Either way, 22 rev. per minute means each minute you go by [tex]22*\frac{440}7=\frac{9680}7[/tex] units per second. Now you got the linear speed, just find out the time by dividing the distance by the speed!
So, what's the unit for the radius?