Endless running chain
A lateral impact is added to the initially static chain so that an wave-shaped movement is created in the chain. You notice that the chain moves up to the wheel, stops there and the chain comes to a standstill again.
Now pull the chain and set it in motion. If you send another wave through the chain by pushing slightly against it, you can observe the following:
As long as the chain stands still, the wave first spreads out and is only stopped at the presumed end of the chain.
Further informationson the exhibit "Endless running chain"
If the chain is then in motion, the wave tries to run up the chain and as the chain keeps following, the wave remains in the same place. Thus we can observe a standing wave.
Of course, the chain does not run forever, because energy is constantly lost through friction.