eli5: Where does energy spent go?

Question

The law of conservation of energy states that energy cant be created nor destroyed, but, when lets say i punch a wall or run i spent some energy, where does that energy go?

In: Physics

Answer 1

The ELI5 answer is sound and heat, unless you broke the wall when punching it, then some of it went into “plastic deformation” or the permanent movement of some material relative to others. The noise is from the sheetrock deflecting or breaking, and that pushing air molecules and starting the vibrations which become sound.

Also, things that move, like the sheetrock and studs behind it, keep vibrating until they are damped out by dissipative forces like friction, and that ends up as heat.