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winterma
Jul6-04, 02:37 PM
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.

AKG
Jul6-04, 02:41 PM
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.

winterma
Jul6-04, 02:54 PM
Got it! Thanks!