Angular velocity and accelerating problem

AI Thread Summary
A disk with a constant angular acceleration of 2.0 rad/s² starts with an initial angular velocity of 5.0 rad/s and rotates through an angle of 11.0 radians. The user expresses confusion over applying the correct formulas for angular motion, noting that they find the problems more challenging than linear ones. Initial attempts to calculate the final angular velocity yielded incorrect results. After receiving guidance, the user acknowledges the need for better understanding of the rotational equations, which parallel linear kinematic equations. The discussion highlights the importance of using the correct formulas in solving angular motion problems.
reaperkid
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Homework Statement



A disk accelerates with a constant angular acceleration of 2.0 rad/s2. If the initial angular velocity is 5.0 rad/s, what is the angular velocity of the disk after rotating though an angle of 11.0 radians?

a = 2 rad/s^2
vo = 5 rad/s
Theta = 11 rad

Homework Equations



a = v^2/r
v = change in theta/change in time

The Attempt at a Solution



I'm very confused on these angular problems. Everyone always tells me that they're just like the linear ones but I disagree. There's something big that I'm missing.

I tried a couple things since I couldn't find a good formula to use.

I tried.. 5 + 1/2(2)(11^2) which is wayy too high I'm thinking.

Then I tried 5 + 2*11 = 27 rad/s.. which is also wrong.

Clearly I'm very confused, can anyone help me on the right track?

Thanks!
 
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LowlyPion said:
Keep in mind that the rotational equations are basically the analog of the linear kinematic equations.

http://hyperphysics.phy-astr.gsu.edu/hbase/rotq.html#drot

Thank you very much! I got it now, I guess I should have searched harder for a good equation.

My fault.
 
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