Circumference of a Circle

C= 3.1416 x 2 x radius

 10" diameter =       31.416” circumference

                                                                2” diameter =  6.2832" circumference

31.416  ¸ 6.2832 = 5

5 : 1 ratio

If “A” turns at  350 rpm’s, “B” will turn at 1750 rpm’s

6’ diameter, C= 18.84961’

18.8496’ x 350 rpm = 6579.36 ft/min

6579.36 ft/min = 395841.6 ft/hr = 74.97 mph

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