Posted by marie darling on .
A truck with 48in.diameter wheels is traveling at 55 mi/h.
Find the angular speed of the wheels in rad/min, *hint convert miles to inches & hours to minutes: __rad/min
How many revolutions per minute do the wheels make?__ rpm

trigonometry 
Reiny,
radius of wheel = 24 inches
one rotation = 2π(24) = 48π inches
in 1 hour it goes 55 miles
= 55x5280x12 inches
= 3484800 inches
number of rotations per hour
= 3484800/(48π) = 23109.29774 rotations per hour
= 385.155 rpm
= 385.155x(2π) radians /min
= 2420 radians/min
check my arithmetic