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

A magnetic computer disk 8.0 cm in diameter is initially at rest. A small dot is painted on the edge of the disk. The disk accelerates at 600 rad/s^2 for .5s, then coasts at a steady angular velocity for another .5s.

A.What is the speed of the dot at t = 1.0 s? 12m/s

b. Through how many revolutions has it turned?

2. Relevant equations

ummm rotational kinematics...this really isn't the issue

3. The attempt at a solution

I was thinking of find theta for the first and second part then adding them, but this did not work. Then i tried to find alpha for the second part 300rad/s^2 then using omega as 300rad/s to get theta at 450

I am stuck on this problem trying to find the revolutions. I tried the above attempt but it was wrong. I know this is pretty easy but the more and more I try I'm getting frustrated and all knowledge seems to fly out the window.

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# Homework Help: Roational motion help

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