Conservation of Energy for Parallel Wires

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Homework Help Overview

The discussion revolves around the conservation of energy in the context of magnetism, specifically involving parallel circuits and the interaction between them. The original poster is exploring how potential energy is created when closing a circuit and its relation to kinetic energy in a second circuit.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • The original poster questions the source of energy when closing Circuit 1 and its effect on Circuit 2, seeking to understand the transition from potential energy to kinetic energy. Some participants suggest thought experiments and resources to aid understanding, while others explore the relationship between induced current and energy conservation.

Discussion Status

The discussion is ongoing, with participants offering thought experiments and external resources to facilitate understanding. There is an exploration of different interpretations regarding the relationship between magnetic flux, induced current, and energy conservation, but no consensus has been reached.

Contextual Notes

The original poster expresses a desire to deepen their understanding of Maxwell's equations and their implications for energy conservation, indicating a potential gap in foundational knowledge that may affect the discussion.

Essence
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Homework Statement


So I'm trying to prove to myself that energy is conserved in the case of magnetism. Here is the set up that I'm using to get that understanding (attached image).

Just to be clear the arrows represent the current lines and I am calculating a gain in PE because if I release Circuit 2 (after closing Circuit 1) I believe it will move in the direction of Circuit 1 (PE turns into KE).

Question: When I close the switch to Circuit 1 I create potential energy for Circuit 2. Where does the energy come from (I presume it comes from the current but don’t see how)?

Homework Equations


I suppose I could list the force equation

F = q v x B
This is really a baseline conceptual question; I already know how to calculate the force (I believe) and everything.

The Attempt at a Solution


N/A (Conceptual Question)
 

Attachments

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    Screen Shot 2015-04-07 at 12.49.39 PM.png
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Dear Essence,

Try the following thought experiment (it might help you.) You have a copper tube, and you drop a copper disk through it. Does the disk fall normally? Is it obstructed?

Hope this helps
 
Try the following video: www.youtube.com/watch?v=keMpUaoA3Tg
 
So this video is a demonstration of induced current due to change in magnetic flux I believe. Are you saying that the law that this relates to will get me to the derivation of where the new potential energy by closing Circuit 1 comes from? Totally possible; just want to check. I believe my teacher mentioned how that law relates to energy conservation when I asked him if there was a more fundamental thought process that combines Maxwell's equations.

I will probably think about it more (because it bothers me that I only understand Maxwell's equations from the standpoint of a technician).

Thanks.
 

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