<PRE><B>Question 914718</B>
A car is moving at a rate of 28 miles per hour, and the diameter of its wheel is about 2 1/3 feet.
A.) find the number of revolutions per minute the wheels are rotating.
B.) find the angular speed of the wheels in radians per minute.
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Find the circumference of the wheel.

C = pi*d = 8pi/3 feet
The car moves 8pi/3 ft per revolution (assuming no slippage or burning of rubber)
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Convert mi/hr to ft/sec
15 mi/hr = 22 ft/sec
28 mi/hr = 28*15/22 = 210/11 ft/sec =~ 19 ft/sec
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rev/sec = 19 ft/sec / 8pi/3 ft/rev
rev/sec = 57/8
rpm = rev/min = (57/8)*60 = 427.5 rpm
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radians/min = 2pi*rev/min
=~ 2686.06 rad/min


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