Conversions of a thrown basebal

[gracemir]

Homework Statement

a good baseball pitcher can throw a baseball toward home plate at 85 mi/h with a spin of 1800 rev/min. how many revolutions does the baseball make on its way to home plate? for simplicity, assume that the 60 ft path is a straight line.

Homework Equations

The Attempt at a Solution

First, we need to convert the unit from miles to feet. Since 1 mile = 5280 feet, 85 mi/h becomes 7480 ft/min.
And we need to do with 1800 rev/min. what should I do with it?

 

[gracemir]

I got it.
1800 * 60 = 108000.
108000 / 7480 = 14.44