Lately I have been thinking about the whole conservation of LINEAR momentum discussion again. Where if you could somehow transfer all the momentum from a big mass to a small mass and have linear momentum conserved you end up with more energy as has already been discussed in the past.
Now the reason why I started thinking about these is because I came across this video from SmarterEveryday:
https://www.youtube.com/watch?v=AnaASTBn_K4
Essentially a bull whip is a momentum transferring device, as the wave moves down the whip the mass of the whip is decreasing and for momentum conservation to hold the speed has to increase and thus the end of a whip ends up breaking the sound barrier.
Now there is no proof that energy was created or that linear momentum is being conserved because like a trebuchet it could be that angular momentum is playing a role here and that it could be the quantity that is conserved which leads to CoE and no free lunch.
This is why I started wondering whether this can't be tested in a longitudinal wave for instance using a conic slinky that has a gradually smaller radius. The momentum in the wave will have to transfer to a smaller and smaller mass which will increase the velocity of the wave and due to the conservation of momentum.
This idea also does not seem crazy as this guy here essentially shows exactly what I'm describing when he changes the pass of the "medium" the wave is traveling through at the second half of the video:
https://www.youtube.com/watch?v=VE520z_ugcU
Conservation of momentum and a conic slinky
Moderator: scott