Answer:
12.1 rev
Step-by-step explanation:
The question seems incomplete. So for simplicity , we assume that the 60 ft trajectory is a straight line.
First, find the time it takes to get the baseball to homeplate:
t = S / V,
where S is the distance traveled
V is the velocity.
t = 60 ft / 85 mi/h
But 1 Mile = 5280 Feet
Therefore
t= 60 / (86 * 5280) =0.0001321 hours
Coverted to minutes
t=hours×60min
= 0.007928 min.
Second, to calculate the number of revolutions made:
N = t × n
t is the time in minutes
n is the number of spin/min
= 0.007928 × 1530
= 12.1300 = approx. 12.1 revolutions.
Answer: 12.1 revolutions.