Why don't perpetual motion machines ever work? - Netta SchrammCheck out our Patreon page: https://www.patreon.com/teded View full lesson: http://ed.ted.com/lessons/why-don-t-perpetual-motion-machines-ever-work-netta-schramm Perpetual motion machines — devices that can do work indefinitely without any external energy source — have captured many inventors’ imaginations because they could totally transform our relationship with energy. There’s just one proble
