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

The turntable of a record player rotates at 33.33rev/min and takes 20.0s to reach this speed from rest. Calculate: a) its angular acceleration, b) the number of revolutions it makes before reaching its final speed.

2. Relevant equations

angular acceleration = angular speed/ time

1 rev = 2pie rad

angular displacement = angular speed x time

3. The attempt at a solution

part a:

I converted the angular speed to rad/s. I solved for angular acceleration, which is delta angular speed divided by time.

3.49rad/s / 20.0s =0.175 rad/s^2Is that correct?

part b:

I used the equation, angular speed = angular displacement/time.

therefore, angular displacement = angular speed x time

3.49rad/s x 20.0s = 69.8rad

I then converted rad into revolutions -->11.1 revolutions. Is that correct??

Thanks

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# Homework Help: Rotational motion of a turntable

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