Problema Solution

a wheel with a radius 6 ft is lowered into water. if the current causes the wheel to rotate at a speed of 8 revolutions per minute what is the speed of the current in miles per hour?

Answer provided by our tutors

The circumference of the wheel is:


C = 2*6*pi


C = 12 pi ft


1 mi = 5280 ft


1 ft = 1/5280 mi


C = (12/5280)pi mi


The speed of the wheel is:


v = 8 revolutions per min


v = 8*C/(1/60) mph (1 min = 1/60 hr)


v = 8*(12/5280)pi/(1/60)


v = 1.09 pi


pi = 3.14


v = 1.09*3.14 mph


v = 3.43 mph


The speed of the current is 3.43 mph.