Angluar acceleration of a computer disk

AI Thread Summary
The discussion revolves around calculating the average angular acceleration of a computer hard disk that spins at 7200 rpm and takes 3.7 seconds to reach this speed from rest. The relevant equation for average angular velocity is provided, which requires the conversion of 7200 rpm to radians per second. Participants emphasize the importance of understanding the variables in the equation and ensuring proper unit conversion. The main challenge highlighted is the initial failure to convert the rotational speed from rpm to rad/s. Accurate calculations are essential for determining the average angular acceleration in rad/s².
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Homework Statement


During normal operation, a computer's hard disk spins at 7200 rpm. If it takes the hard disk 3.7 s to reach this angular velocity starting from rest, what is the average angular acceleration of the hard disk in rad/s2?


Homework Equations



Wav = \varthetaf - \varthetai/Tf-Ti

The Attempt at a Solution

 
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cstout said:

Homework Statement


During normal operation, a computer's hard disk spins at 7200 rpm. If it takes the hard disk 3.7 s to reach this angular velocity starting from rest, what is the average angular acceleration of the hard disk in rad/s2?


Homework Equations



Wav = \varthetaf - \varthetai/Tf-Ti

you want: Wav = (\varthetaf - \varthetai)/(Tf-Ti)

Do you know what all the variables in this equation mean? It is the right equation so you just have to find out what all the variable are in express them in the right units
 
I got it now, I didn't convert the 7200 rpm to rad/s
 

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