Where does the energy go if I raise and lower a block?

HallsofIvy

Basically, it is inefficiencies in your muscle that account for your not getting the energy "back". It goes into increased heat in your body, a little increased heat in the air, because of air resistance, and, if you let the block hit the ground "hard", increased heat in the ground and block.

Generally, the answer to "where does the energy go" is "into heat".

HallsofIvy Recognitions: Gold Member Science Advisor Staff Emeritus	Basically, it is inefficiencies in your muscle that account for your not getting the energy "back". It goes into increased heat in your body, a little increased heat in the air, because of air resistance, and, if you let the block hit the ground "hard", increased heat in the ground and block. Generally, the answer to "where does the energy go" is "into heat".