Question

Why does a nail become warmer when hammered into a plank.

Answer 1

A nail becomes warm when hammered into a plank because evertime the hammer hits the nail, the kinetic energy of the hammer gets transferred to the nail. This energy transfer can be seen through the motion of the nail into the plank, the sound that is created every time the nail is hammered and the heat produced i.e., the nail becoming warmer.
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