Quite an unnecessary, mean-spirited, and mistaken edit. OP, your confusion is perfectly normal. I came here to post that my dad would think this is a perpetual

Quite an unnecessary, mean-spirited, and mistaken edit. OP, your confusion is perfectly normal. I came here to post that my dad would think this is a perpetual motion machine. He simply is not familiar with the physical laws that make such a thing impossible and likes the idea of it.