# Karate

Is it easier for the person on the left to break a uniform wooden board of length $$l$$, which has a mass $$m$$ than to break a uniform wooden board of twice the length $$2l$$ and twice the mass $$2m$$?

Note: Both are equivalent in thickness, density, etc. The person doing the kicking contacts the center of the boards in both cases. Assume that, if the board breaks, it breaks almost immediately after the collision.

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