Acceleration at the center of circle

AI Thread Summary
The discussion focuses on calculating the acceleration at the center and at 1 cm from the center of a rotating circle with a radius of 2 cm and a rotation speed of 1000 rpm. It is established that the acceleration at the center is zero since it does not move. For the acceleration at 1 cm from the center, there is confusion regarding the correct application of formulas, with a participant incorrectly using the wrong radius and angular velocity. The provided acceleration value of 2 m/s² at the rim is questioned as being inconsistent with the theoretical calculations. Overall, participants express uncertainty about the problem's parameters and calculations.
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Homework Statement


A circle with radius 2 cm rotates at 1000 rpm and the acceleration at the rim is 2 ms-2.
a. What is the acceleration at the center ?
b. What is the acceleration at 1 cm from the center ?


Homework Equations





The Attempt at a Solution


a. The acceleration will be zero because the center doesn't move?

b. a = ω2r = 2πf*r = 2π * 1000/60 * 2 x 10-2 = 2/3 π ms-2. Is this right?

Thanks
 
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Your answer for a seems to be right. The problem is that the acceleration at the rim of a circle with radius 2 cm that rotates with 1000 rpm is more than 100 times as high as 2 m s^{-2}
I don't see why the acceleration is given at all in the problem.

For part b you use \omega instead of \omega^2 and a radius of 2 cm instead of 1 cm
 
Hi willem

Yeah, my mistake...now I know it's not a good idea to post question at 2 AM..

I also agree that the information given doesn't match the theoretical calculation...something wrong with the question...

Thanks a lot !
 
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