- #1

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## Homework Statement

Problem with diagram here

## Homework Equations

I=(1/3)MR

^{2}(I believe the formula given in the problem is incorrect since it is pivoting on one end rather than the center of mass)

KE=(1/2)Iω

^{2}+(1/2)Mv

^{2}

L=Iω=MvR

## The Attempt at a Solution

a.

True, the velocity is still going in the same direction at the instant of the collision.

False, it is a perfectly inelastic collision, which means kinetic energy is not conserved.

True, no real reason why. I just think it's true? No forces seem to be working on the center of mass during the collision.

True, no external forces/torque are working on the collision at that moment.

b.

(M/3)Lv=(1/3)ML

^{2}ω+(M/3)ML

^{2}ω

(M/3)Lv=(2/3)ML

^{2}ω

v/(2L)=ω

c.

KE=(1/2)Mv

^{2}+(1/2)I

_{cm}ω

^{2}

I have no idea how to approach this correctly other than the possible use of the parallel axis theorem. This was as far as I got

The answer is given: (5/6)MgL+(1/12)Mv

^{2}

Can someone please explain to me the steps to get to that answer?