# Homework Help: Heat generated due to motion of wire in magnetic field

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1. Apr 4, 2016

### Titan97

1. The problem statement, all variables and given/known data
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?

2. Relevant equations
$V=BLv$

3. 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?

2. Apr 4, 2016

### andrevdh

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: Apr 4, 2016
3. Apr 4, 2016

### Titan97

But according to the given answer given, no heat energy is produced.

4. Apr 4, 2016

### cnh1995

That is true. The movement of charges takes place for a very short time, which is negligibly small. So, as far as highschool physics is concerned, I believe the answer given is correct.