Heat generated due to motion of wire in magnetic field

AI Thread Summary
When a wire moves through a magnetic field, an induced EMF causes charge accumulation at the ends of the wire, suggesting heat energy generation. However, since current only flows in closed loops and the induced current is momentary, the overall current is effectively zero, leading to no heat generation according to the formula P=i^2R. The discussion concludes that while charge movement occurs briefly, it is negligible in terms of thermal energy production. Thus, for high school physics, the consensus is that no significant heat energy is generated in this scenario. The explanation aligns with fundamental principles of electromagnetism and circuit theory.
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.
 
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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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