Faraday's law and perpetual motion

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    Faraday's law Law
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Homework Help Overview

The discussion revolves around Faraday's law of electromagnetic induction and its implications regarding perpetual motion. Participants are examining the effects of a hypothetical positive sign in Faraday's law and its relationship to the conservation of energy.

Discussion Character

  • Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants are exploring whether a positive sign in Faraday's law would lead to perpetual motion, questioning the implications for energy conservation and the nature of induced currents.

Discussion Status

Some participants express agreement with the notion that a positive sign could lead to a scenario violating conservation laws, while others provide examples to illustrate their points. Multiple interpretations of the concept of perpetual motion are being explored.

Contextual Notes

There is a distinction made between a test question and a homework question, indicating the context of the discussion may be more formal or evaluative in nature.

Princess19
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If a positive sign were present in Faraday's law instead of a negative sign, this would lead to perpetual motion..

True or false?
 
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Is this a homework question?
 
no, its a test question and i want to see if i got it right :)
 
perpetual motion of?
 
I think the answer is true, since the sign is positive, it doesn't oppose the change in magnetic flux, therefore violating the law of conservation of energy, and itll never stop moving as it increases in velocity.
 
Agreed. Consider a wire ring in a changing magnetic field. The induced emf would generate a current whose magnetic field reinforced (instead of opposed) the external field, creating positive feedback. I wouldn't call that perpetual motion exactly, but in spirit "True" is the right answer.
 

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