Question 1045458
Convert mi/hr to in/min
[ 55 mi/hr ] x [ 1/60 hr/mins ] x [ 5280 ft/mi ] x [ 12 in/ft ]
{{{ 55*( 1/60 )*5280*12 = 58080 }}} in/min
---------------------------
How many times does the circumference,  C, of the 
wheel go into this number?
{{{ C = 2*pi*30 }}}
{{{ C = 60*pi }}}
------------------
[ in / min ] / [ in/C ] = [ C/min ]
{{{ 58080 / ( 60*pi ) = 968/pi }}} C/min
and
[ C/min ] x [ radians/C ] = radians/min ]
{{{ ( 968/pi )*( 2*pi ) = 1936 }}} radians/min
The angular speed of the wheels is 1,936 radians/min
----------------------
[ revolutions/min ] = [ radians/min ] x [ 1C/radians ]
{{{ 1936*( 1/(2*pi) ) = 308.124 }}}
The wheel makes 308.124 revs/min
------------------------------
Check my math & get a 2nd opinion, too