How Do You Calculate Angular Acceleration from RPMs?

AI Thread Summary
To calculate angular acceleration from RPMs, the initial poster attempted to convert 13164 RPM to radians per second, resulting in 1378.5 rad/s. They sought clarification on how to compute angular acceleration, which is defined as the change in angular velocity over time. The listed answer of 3.791 rad/s² was questioned due to confusion over the calculations. Further investigation revealed that the source of the problem contained inaccuracies, leading to frustration with the provided answers. The discussion highlights the importance of verifying the accuracy of practice problems from online resources.
ginaoh
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Can someone walk me through this problem?

A power drill reaches 13164 rpm in 1.01 seconds. What is the angular acceleration?

The answer listed is 3.791 rad/s2, but I don't know how to get there.

So far, I did (13164 rev x 2pi)/60 seconds to get 1378.5 rad/s (which is 'w', right)? but change in 'w' from 0-1378.5 / change in 't' from 0-1.01s isn't right.
Please help.
 
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The listed answer makes no sense. Are you stating the problem completely?
 
angular acceleration problem

Thanks for responding. I found this problem on a site for practice problems (link listed below). I copied and pasted the question and answer directly from the page. I am confused.


www.dctech.com
 
I went to that site and looked at 3 problems. Only one gave the correct answer; two, gave goofy answers, just like the problem you presented. Forget it. (You may wish to complain to the site owners.)
 
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