The radius of a car wheel is 15 inches. How many revolutions per minute is the wheel making when the car is traveling at 60 mph?

AdamTaurus
Jan 30, 2018

#1**+2 **

60 m/hr x 5280 feet/m x 12 in/ft x 1 hr/60min = 63360 in/min

Circumference = pi x 2r = pi x 30 = 94.2477 inches/circumf

63360 in /min x 1 circumf/94.2477 inches = 672.27 circumf/min = rpm

ElectricPavlov
Jan 30, 2018

#1**+2 **

Best Answer

60 m/hr x 5280 feet/m x 12 in/ft x 1 hr/60min = 63360 in/min

Circumference = pi x 2r = pi x 30 = 94.2477 inches/circumf

63360 in /min x 1 circumf/94.2477 inches = 672.27 circumf/min = rpm

ElectricPavlov
Jan 30, 2018

#3**+2 **

Great! If we BOTH got the same answer, it is likely I got the right answer too! Thanx !

ElectricPavlov
Jan 30, 2018