If a mechanism doesn't loose GPE then there's no intent for the wheel (or mechanism) to rotate (example: Roberval). Therefore I think it should "borrow" or loose some height which should be restored after a complete cycle.KAS wrote:"The minute a weight or weights on a wheel lose height, even by the slightest amount, the wheel will not turn perpetually as the combined mass preservation would be compromised and a reset would become impossible.
The scissor-mechanism I posted in the other thread can be adjusted (by adding a spring for example) to let it rotate 3.9.. times from that depicted position, even though that spring is not pre-loaded. You are correct it's not a winner, as on close examination the top weight had lost a small amount of height at each cycle -that was a bit disappointing-
What do you mean by "Normal Force" by the way (not its technical but your alternate meaning): My guess, the attempt of turning GPE against itself?I assure you that this "Normal Force" is evident and accessible.