how come different sounds are made when you hit different objects together, when in reality, the two objects aren't even touching (due to the repulsion of the electrons that make up the objects). and what is a sound wave? it cant just be the movement of air because then we would here different sounds all the time when it was windy, right? also, is heat created due to the movement of atoms, or the vibrations of atoms? if its just movement, wouldn't windy days be hotter than they are? these are probably really stupid questions, but i was just curious.