(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Starting from rest, a 12cm diameter compact disk takes 2.7s to reach its operating angular velocity of 2005rpm. Assume that the angular acceleration is constant. The disk's moment of inertia is 2.5 x 10-5 kgm^2.

a.) How much torque is applied to the disk?

b.) How many revolutions does it make before reaching full speed?

2. Relevant equations

t=I(alpha)

3. The attempt at a solution

For part a I used t = I(delta w/delta t). I found w by finding the frequency (33.417rev/s), and then I plugged f into w = (2pi radians)f to get 209.965. I then found torque to be 1.944 x 10-3 Nm. I am unsure of how to solve for part b.

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# Homework Help: Finding the number of revolutions

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