When Alicia and Zoe ride a carousel, Alcia always selects a horse on the outside row, whereas Zoe prefers the row closest to the center. These rows are 19 ft 3 in and 13 ft 11 in from the center, respectively. The angular speed of the carousel is 2.4 revolutions per minute. What is the difference, in miles per hour, in the linear speeds of alicia and Zoe?
I got something like 2.193, but the book says it is .92. Help please! I'll pick a best answer TODAY!!!!!!
2007-09-19 06:49:36 · 3 answers · asked by James J 2 in Science & Mathematics ➔ Mathematics
2.4 rpm = 144 rev per hour
For Alicia 1 revolution =2 pi19.25 ft = 120.95 ft
So total distance traveled in 144 revolutions is 17416.99 ft
So speed = 3.3 mph
For Zoe the speed is 2pi*(13 11/12)2.4= 12591.5 ft/min
= 2,38mph
So I get a difference of = .92mph
2007-09-19 07:46:25 · answer #1 · answered by ironduke8159 7 · 0⤊ 0⤋
I also get .92.
Looking at your answer, it looks like you're off by a factor of.. 2.4. Does that number look familiar? I think you calculated it for 1 revolution happening in a minute, instead of 2.4 revolutions in a minute..
2007-09-19 07:16:25 · answer #2 · answered by Hey it's Ken! 3 · 0⤊ 0⤋
C=πd
Alicia = 2*19.25π'*2.4rev/min*60/5280min/mile
Zoe = 2*(13 11/12)π'*2.4rev/min*60/5280min/mile
Alicia = 3.30 miles/hour
Zoe = 2.38miles/hr
difference =3.3-2.38=.92 mph
2007-09-19 07:10:27 · answer #3 · answered by chasrmck 6 · 0⤊ 0⤋