SOLUTION: A truck with 20-in.-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

Algebra ->  Trigonometry-basics -> SOLUTION: A truck with 20-in.-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       Log On


   

Question 1014569: A truck with 20-in.-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
Answer by FrankM(1040) About Me  (Show Source):
You can put this solution on YOUR website!
55+mi%2Fhr * 5280+ft%2Fmi * 12+in%2Fft*1hr%2F60+min*1+rad%2F10in = 5808rad%2Fmin

To understand the method above, keep in mind, the unit must be lined up correctly, i.e. to convert from one unit to another, they must not be both in the numerator or denominator. So for example:
55+mi%2Fhr * 5280+ft%2Fmi
miles will cancel and we are left with ft%2Fhr
Last, a radian is simply the angle whose arc covers the distance of one radius. Here, 10 inches.