Physics and Rotational Motion

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MDToBeInNC

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Here's the question:

Ball is rolling without slipping along a flat surface at linear Velocity V1. It then goes up an incline with Heigh h and then rolls along another flat surface at height h. The problem wants to know what the new linear velocity will be.
I know this is a conservation of energy problem so U1+K1=U2+K2 where U1=0 and U2=mgh.
My initial assumption is that both the linear KE and the rotational KE would change as it went up to the new height but the problem does not give me any info like angular speed so I can't calculate any change in rotational energy. Does this mean that I'm wrong in thinking that rotational energy changes? Or put another way, that the rotational energy is just like a constant and all I need to do is calc the change in linear KE based on the change in potential E (mgh)?
Thanks for any enlightenment :)

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I believe that you're right to think that angular momentum is conserved (there is no net torque applied) but without them supplying you with the dimensions to let you calculate the first moment of inertia or the initial angular velocity I don't see how they expect you to account for it. Are the answer choices actual numbers or just expressions?

But maybe I'm wrong. I'm sure someone else will chime in if so :)
 
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