What is the Formula for Calculating Angular Deceleration in College Physics?

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To calculate the angle through which a flywheel turns as it decelerates from an angular speed of 117 rad/sec to rest, the formula w^2 = wo^2 + 2a(theta) is used, where w is the final angular speed (0 rad/sec), wo is the initial angular speed (117 rad/sec), and a is the angular deceleration (-2.5 rad/sec^2). The discussion highlights that using this formula correctly will yield a non-zero angle. For finding the time required to come to rest, another kinematic equation analogous to linear motion equations can be applied, utilizing the known values of w, wo, and a. Participants emphasize the importance of correctly applying these formulas to solve the problems. Understanding these concepts is crucial for mastering angular motion in physics.
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A flywheel has a constant angular deceleration of 2.5 rad/sec^2. I need to ...

1. find the angle through which the flywheel turns as it comes to rest from an angular speed of 117 rad/sec.

2. Find the time required for the flywheel to come to rest.

So i used the formula w^2=wo^2+2a(theta) since w^2 is 0, that would make theta 0, which is not possible.
 
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So i used the formula w^2=wo^2+2a(theta) since w^2 is 0, that would make theta 0, which is not possible.
What in the world makes you say that?
w = 0 rad/sec
wo = 117 rad/sec
a = -2.5 rad/sec^2
So solve for theta.
There's another simple equation you can use to answer part 2. You have w, wo, and a, and you need to find t. I'm sure you can find the formula in your book somewhere. If not, it is analogous to one of your 5 basic kinematic equations, simply replacing linear measurements for corresponding angular ones, so if you can't find it, you should be able to figure it out.
 
Thank you

Got it! Thanks!
 
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