How many Rpms?

Question

for a wheel 1 and 5/8 inches in diameter traveling at 10mph?

Answer 1

1.625 inches is a diameter of (*π) of 5.1" or 0.425 ft

10 mph * 5280 ft/mi * 1hr/60min = 880 ft/min

so how many rotations of 0.425 ft are in 880 ft

880/0.425 = 2,070 rotations/min, which is RPM

sorry Mike, your solution is too complicated.

Answer 2

1.625" times Pi gives 5.105" circumference.

that is 8.05727283 × 10-5 miles circumference

divided into 10 miles gives

10 / (((1.62500 * pi) / 12) / 5 280) = 124 111.473 rph

divide by 60 to get rpm

  (10 / (((1.62500 * pi) / 12) / 5 280)) / 60 = 2,068.52455 rpm