How Many Revolutions Does a CD Make When Stopping?

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SUMMARY

The discussion centers on calculating the number of complete revolutions a CD makes as it comes to a stop, given an angular displacement of 68.1 radians. The initial calculation suggests that the number of revolutions is 107, derived from the formula \(\frac{68.1}{2\pi}\). However, this result is disputed as incorrect according to the textbook, prompting a reevaluation of the division process. The correct answer must be an integer, indicating a potential error in rounding or calculation.

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  • Understanding of angular displacement and its units
  • Familiarity with the relationship between radians and revolutions
  • Basic proficiency in division and rounding techniques
  • Knowledge of physics concepts related to rotational motion
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Students studying physics, particularly those focusing on rotational dynamics, as well as educators seeking to clarify concepts related to angular motion and calculations.

Paymemoney
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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 [tex]\frac{68.1}{2\pi}[/tex] = 107 revolutions

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

P.S
 
Last edited:
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Check your division.
 
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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