- #1
tcc88
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Homework Statement
An athlete swings a ball, connected to the end of a chain, in a horizontal circle. The athlete is able to rotate the ball at the rate of 8.16 rev/s when the length of the chain is 0.600 m. When he increases the length to 0.900 m, he is able to rotate the ball only 6.32 rev/s.
(a) Which rate of rotation gives the greater speed for the ball? [Which I got is 6.32]
(b) What is the centripetal acceleration of the ball at 8.16 rev/s? [?]
(c) What is the centripetal acceleration at 6.32 rev/s? [?]
Homework Equations
a[c] = v^2/r
T = 2∏r/v
The Attempt at a Solution
I know the I need to find the velocity to solve this question, but that is where I am having trouble. I am assuming 8.16 and 6.32 are the periods. So I get:
v = 2∏(0.300)/(8.16) for B; and then use this to find acceleration which is: a[c] = (0.23)^2/(0.300) = 1.176. But this is not the correct answer! Why?