Angular Acceleration: Solve 500-700rev/sec in 30sec

AI Thread Summary
The discussion focuses on calculating the average angular acceleration of a fan that speeds up from 500 to 700 revolutions per second in a specified time. The initial calculation presented was incorrect due to a misinterpretation of the time duration, which should be 3 seconds instead of 30. The correct formula for angular acceleration is applied, resulting in an average angular acceleration of 418.9 rad/s². The conversion from revolutions to radians is clarified, emphasizing the importance of unit consistency. The final consensus confirms the corrected calculation based on the accurate time frame.
Sparky500
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Homework Statement



A fan increases in speed from 500 to 700rev/sec in 30 seconds. What is the average angular acceleration during that time?


Homework Equations





The Attempt at a Solution



The answer i get for this one is

∝=(700-500 rev⁄sec)/3sec

any input appreciated
 
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well, same problem again.

1. the angular acceleration has the units of rad/s^2
2. how many rad is 200 rev?
 
sorry i have given the wrong answer for you to look at, the correct answer (one i have) should have read:

=418.9 rad⁄s^2
 
200 * 2pi / 30 = 41.89 ...
 
hi, just noticed that i had a misprint in my original question above (sorry about this) in the question it says 30 secs whereas it should read 3.0 secs.
therefore would my original answer be the correct one (sorry)
 

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