Calculating Average Acceleration in Uniform Circular Motion

AI Thread Summary
In uniform circular motion, the average acceleration over one complete cycle (time T) is zero because the initial and final velocities are equal, resulting in no change in velocity. However, over half a cycle (time T/2), the average acceleration is non-zero since the velocities are equal in magnitude but opposite in direction. The change in velocity is calculated as twice the magnitude of the velocity, leading to a formula for average acceleration of (8πr)/T². The calculations appear correct, confirming the understanding of average acceleration in circular motion. This analysis highlights the distinction between average acceleration over different time intervals in circular motion.
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I've been working on this for awhile. I think I've got it. Ok here's the problem:

A particle moves in a circle of radius r completing one cycle in time T. What is the magnitude of the average acceleration over time T and over time T/2?

It seems to me that over time T the magitude of the ave acceleration should be zero, but over time T/2, it has to be a non-zero number. Since the acceleration is constant, the instantaneous acceleration should be equal to the average acceleration. v(final)-v(initial)=change in v

the (change in v)/(change in time)= a ; so at time T, v(final) - v(initial)=0 and so acceleration has to equal zero. Over time T/2, v(final ) and v(initial) are equal in magnitude but opposite in direction, so the change in v
should equal (2)(magnitude of v)

v=(2(pi)r)/T, then delta v = (4(pi)r)/T, delta t=T/2, so a=((8)(pi)r)/T^2
This seems right to me. Am I missing something.
 
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looks fine to me.
 
Thanks for the help.
 
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