I How Does Lenz's Law Relate to Magnetic Flux and Induced Currents?

AI Thread Summary
When two magnets with like poles face each other and move through a copper coil, they will still demonstrate the dampening effect of Lenz's law, which opposes the motion of the magnets. The current induced in the coil will alternate direction as the magnets move, creating resistance to their motion. There is no net current in one direction due to the equal flux contributions from both south poles. The key factor is whether there is a change in magnetic flux through the coil as the magnets move. Overall, Lenz's law remains applicable in this setup, preventing perpetual motion.
rayjbryant
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If I have two magnets attached with like poles facing each other, will they still exhibit the dampening effect of Lenz's law when moved through a copper coil?
I've attached an illustration of my set up.
 

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rayjbryant said:
Summary: If I have two magnets attached with like poles facing each other, will they still exhibit the dampening effect of Lenz's law when moved through a copper coil?

I've attached an illustration of my set up.
Lenz's law is always obeyed. Otherwise you'D HAVE A PERPETUAL-MOTION MACHINE. tHERE IS NO FREE LUNCH.

iN YOUR CASE THE CURRENT THRU THE COIL WOULD FIRST GO ONE WAY, THEN THE OTHER, ALWAYS SUCH AS TO RESIST THE MAGNETS' MOTION.
 
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Would there be a net current in one direction do to greater flux density of the South poles?
 
rayjbryant said:
Would there be a net current in one direction do to greater flux density of the South poles?
Because the two south poles face each other? No, because the flux between the two south poles is the sum of the flux due to each south pole.
 
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rayjbryant said:
Summary: If I have two magnets attached with like poles facing each other, will they still exhibit the dampening effect of Lenz's law when moved through a copper coil?

I've attached an illustration of my set up.

I will ask you this: Is there any magnetic flux change through the coil as the magnets move through it?

Zz.
 
Good question.
Assuming the magnets are far away from the coil, move into then out of the coil in the opposite (could also be in the same) direction so the flux is initially and finally zero, then my hint is what you undoubtedly already know:
## \int_a^b f'(x) \, dx = f(b) - f(a) ## :smile:
 
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