To be honest, the movement of objects with sound is quite logical. If you look at sound, one way or another, its the movement of atoms and molecules (which is air) yeah?
Movement is energy, and energy has an equilivent mass. (proved by E=MC2) Thus, if enough air is displaced in one direction at once against a solid object, the energy transfurred will be, in theory, the same as the kenetic force of the first object!

If that made sence... I hope it did.