MAC 1114 Pre calc trig

Question

A truck with 34-in.-diameter wheels is traveling at 50 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

Round your answers to 1 decimal place.

Answer 1

For radians per minute I get 3105.9 radians per minute. I get that by determining the car goes 52800 inches/min, and then I created a calculation of (52800/34(pi)) x 2(pi). The first part determines the number of revolutions per minute because 34(pi) is the circumference of the wheel. 2(pi) is the number of radians in a circle. That calculation simplifies to 52800/17 which is 3105.9 rounded to the nearest tenth.

For revolutions per minute I get 494.3 revolutions per minute, from the above term of 52800/34(pi).