- #1

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- Homework Statement
- A plank of length 2l and mass M lies on a frictionless plane.

A ball of mass m a nd speed Vo strikes its end as shown. Find the final

velocity of the ball, vf, assuming that mechanical energy is conserved

and that vf is along the original line of motion

- Relevant Equations
- All below.

IS my solution right? Comparing with the other solutions, the answer just exchange the signals, i don't know why,

THats what ifound.

And here is the three equations:

{i use the point which occurs the collision}

Lo = Lf >>

Eg = ct>

I = ml²/3

P = cte

I just assumed that xyz dextrogira, i thought that putting by this way, the math would implies the correct values, that is, we would find w<0, and the others values. Apparently i am wrong in something, where?

And here is the three equations:

{i use the point which occurs the collision}

Lo = Lf >>

*0 = Iw + M*Vcm(block)*Eg = ct>

*mvo² = mvf² + MVcm² + Iw²*I = ml²/3

P = cte

*mvo = mvf + MVcm*I just assumed that xyz dextrogira, i thought that putting by this way, the math would implies the correct values, that is, we would find w<0, and the others values. Apparently i am wrong in something, where?