Heat generated due to motion of wire in magnetic field

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Homework Help Overview

The discussion revolves around the generation of thermal energy in a wire moved through a magnetic field, specifically addressing the conditions under which heat is produced due to induced electromotive force (EMF) and current flow.

Discussion Character

  • Exploratory, Assumption checking, Conceptual clarification

Approaches and Questions Raised

  • Participants explore the relationship between induced EMF and charge movement in the wire, questioning whether this leads to heat generation. There is a discussion on the necessity of a closed loop for current flow and the implications of transient charge movement.

Discussion Status

The conversation reflects differing interpretations of the problem, with some participants suggesting that heat may be generated during transient charge movement, while others assert that no heat is produced due to the lack of sustained current. The discussion remains open without a clear consensus.

Contextual Notes

Participants reference high school physics principles and the conditions under which current flows, indicating a focus on foundational concepts and potential misconceptions regarding induced current and heat generation.

Titan97
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Homework Statement


A wire is moved with constant velocity such that the motion is perpendicular to the length of the wire in a region containing magnetic field perpendicular to the plane of motion. The wire has a resistance R. Will thermel energy be generated in the wire?

Homework Equations


##V=BLv##

The Attempt at a Solution


Due to induced EMF, positive charges accumulate on one end and negative charge accumulated on the other end. Since the process involves motion of charges (current), then heat energy will be generated.

But in an alternative explanation, current flows only in closed loops. So according to ##P=i^2R##, since ##i=0##, heat energy will not be generated. Which answer is correct?
 
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I think you have answered it in the first answer, since combining it with the second one there will be a short period during which there will be charge (electrons) motioning towards the one end of the wire. That is the electrons will collide with some of the atoms as they move towards the one end of the wire.
 
Last edited:
But according to the given answer given, no heat energy is produced.
 
Titan97 said:
But in an alternative explanation, current flows only in closed loops. So according to P=i2RP=i2RP=i^2R, since i=0i=0i=0, heat energy will not be generated. Which answer is correct?
That is true. The movement of charges takes place for a very short time, which is negligibly small. So, as far as high school physics is concerned, I believe the answer given is correct.
 

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