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Flux Cutting and Electromagnetic Induction

Hi all

I was wondering what exactly happens to a conductor when it cuts lines of flux? Does doing so provide a force that acts on the electrons in the conductor?
Induces an emf and force (the direction of which is opposite to the motion of the change that caused it)
Original post by Mowerharvey
Hi all

I was wondering what exactly happens to a conductor when it cuts lines of flux? Does doing so provide a force that acts on the electrons in the conductor?


Electrons are force carrying particles. They are attracted to other unlike charges or repelled by the same charge.

Magnetism is the electric charge force as manifested by moving charges relative to each other.

The free mobile electrons in a conductor will react to the magnetic field. If the field is changed as happens when a conductor cuts the field lines, or, of the field itself changes, then the mobile electrons of the conductor will be repelled or attracted by that field accordingly. In other words, the mobile electrons of the conductor can only react to the charge force which is indistinguishable between a changing magnetic field with a stationary conductor or a moving conductor in a static field.

The magnetic field will try to hold the conductor electrons in position in space. The motion of the conductor will cause the bunching of charge because the electrons have run out of room to stay in position. (Think about iron filings on a piece of paper with a magnet underneath as being analogous to electrons. If the paper is moved, the filings stay in position relative to the magnet but not the paper. On the other hand if the magnet is moved relative to the paper, again the filings will move under the influence of the magnet. Same with electrons in a conductor.)

Any moving charge is defined as an electric current.

The induced voltage in that conductor is a measure of the magnitude of the magnetic field coupling with the bulk of electrons in the conductor AND the velocity of the conductor relative to the magnetic field AND the amount of charge in the conductor in the field! All conspire to create a charge-pressure against anything that resists the movement.
(edited 7 years ago)

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