I Magnet through Pipe Experiment, continued

AI Thread Summary
The discussion centers on how a falling magnet induces currents in a pipe, which slows its descent due to the changing magnetic field. Participants explore the momentum of these induced currents and question how it dissipates after the magnet exits the pipe. There is a debate on whether the system behaves similarly to an LC circuit and whether quantum mechanics is relevant to understanding the electron momentum involved. Some contributors assert that classical electrodynamics sufficiently explains the phenomenon without invoking quantum physics. The conversation highlights the interplay between induced currents and external forces affecting the system's momentum.
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The changing magnetic field of a falling magnet induces currents in the pipe that slows it's fall through the pipe.

Question:
If the induced currents are decreasing the magnets descent then they must themselves have momentum. How is it dissipated once the magnet has passed through the end of the pipe? Does it simply oscillate similar to an lc circuit?
 
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The pipe in which current take place undertakes force downward. One should apply upward force from outside so that it does not move.
 
anuttarasammyak said:
The pipe in which current take place undertakes force downward. One should apply upward force from outside so that it does not move.
That applied force increases the momentum that is carried in the currents induced by the magnet. If they were both free falling then technically it would be the same as them being stationary. I'm asking if the magnet exciting the pipe is similar to interrupting dc current.
 
I think we're in the realm of quantum physics when we deal with electron momentum.
 
rude man said:
I think we're in the realm of quantum physics when we deal with electron momentum.
There's no quantum mechanics required for this problem - we're working with bulk currents and properties of matter that are adequately described by classical electrodynamics.
 
Quoting the OP: "That applied force increases the momentum that is carried in the currents induced by the magnet."

Clearly he was referring to the momentum carried by the electrons, not the magnet. It's a subject for quantum physics.
 
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