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- Homework Statement
- What is the total kinetic energy of this body that is made of 3 identic mass m and massless rods?

- Relevant Equations
- kinetic energy

This is my answer:

$$KE_{total}=KE_{centermass}+KE_{uppermass}+KE_{bottommass}$$

$$KE_{total} = \frac 1 2 (mv^2 + 2m(\vec {v} + \vec {wL})^2) $$

But, the solution manual says that the answer is this:

$$KE_{total} = \frac 1 2 (mv^2 + 2m(v^2+w^2L^2)) $$

I think he regard this composite body as an ordinary rigid body (e.g a pancake),However, the angular velocity of the upper and lower mass has different direction. So, I doubt that this is correct.

What do you think?

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