How Many Revolutions Does a CD Make When Stopping?

Thread starter Paymemoney
Start date Apr 6, 2010

AI Thread Summary

The discussion centers on calculating the number of complete revolutions a CD makes while stopping, with an angular displacement of 68.1 radians. The initial calculation suggests dividing 68.1 by 2π, resulting in approximately 10.83 revolutions, which is then rounded to 11. However, this answer is deemed incorrect according to the textbook. Participants emphasize the need for accurate division and confirm that the final answer should be an integer. The conversation highlights the importance of precise calculations in physics problems.

Apr 6, 2010

Paymemoney

Homework Statement

How many complete revolutions does the CD make as it spins to a stop?

The Attempt at a Solution

I already know that the Angular displacement is 68.1 rad

The answer is \frac{68.1}{2\pi} = 107 revolutions

however this is incorrect according to the book's answer's

P.S

Last edited: Apr 6, 2010

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Apr 6, 2010

nnnm4

Check your division.

Apr 6, 2010

Paymemoney

it gives me 10.83,i round it up to 11 and it is still incorrect.

by the way the answer should be integer.

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