Magnets and Work on Current Loops

Most recent answer: 10/11/2013

Q:
what happens to electron in current carrying wire in magnetic field...is it the force on these electrons or on the wire by external magnetic field and as we say no work is done by magnetic field on moving charges but does it do the work on the wire... if yes then what type of force is it...
- vishal (age 16)
Jodhpur,rajasthan,india
A:

As you can read above, the work done, meaning the transfer of energy from current loops to mechanical motions, occurs as the charge-carriers (electrons) bounce off surfaces or other scatterers in the wire. The magnetic field does no work directly (ignoring spin effects), but changes the distribution of directions of those bounces, thus causing the energy tranfer to occur. The type of force involved in the electron scattering events is ordinarily just an electrostatic force. The way it shows up is usually far from classical, since the things that scatter are extended quantum waves, but the force remains primarily electrostatic in most cases.

Mike W.


(published on 10/11/2013)