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Is Electric Current Induced In A Wire When It Is Moving Perpendicularly To The Magnetic Lines Of Force Or When It Is Moving In Line With Them?

electromagnetism electric current induction electrical engineering physics

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#1 MitkoGorgiev



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Posted 02 February 2020 - 04:03 AM

One of the consequences which is derived from the Faraday’s law of induction is the following: when a metal wire is moving in a magnetic field, then the component of the wire’s velocity which is perpendicular to the magnetic lines of force should be the cause for the induced current in it. Since the Faraday’s law of induction is not true (please see http://www.sciencefo...induction-true/), this consequence is also untrue. The actual cause for the current in the wire is the component of its velocity which is in line with the magnetic lines of force.

Consider this well-known and most effective experiment: we move a magnet in and out of a solenoid. Instead of moving the magnet, we can do the opposite – move the solenoid, so to say, in and out of the magnet.
In the second case the question is: Is the wire of the solenoid moving perpendicular to the magnetic lines of force, or is it moving in line with them?
It is obvious that the wire of the solenoid is moving in line with the magnetic lines of force. And, as I said, this is the most effective way of inducing electric current in a wire.

Please watch now this YouTube video, where seemingly it is demonstrated that current is induced in the wire when it is moving perpendicularly to the magnetic field.


The magnet used in the video has approximately the following shape (figure a):

horse shoe magnets.gif

Why is some weak current induced in the moving wire? It is not because of its motion through the magnetic field marked with the four horizontal arrows, but because of the ‘components’ of the magnetic field marked with vertical red and blue arrow.
Please look at the figure b. Parts of the first magnet are cut off and now the magnetic field has a different form with more upright ‘components’. If the wire is moving through this field with the same velocity as before, then the induced current in it will be greater.

Let’s look now at this drawing:

separate identical magnets.gif

In this drawing there are two separate identical magnets, placed so that the magnetic field between them is the same as in the figure(a) above. When the wire is moving down through this magnetic field, then it should happen the same as in the case of figure(a). But no, in this wire no current will be induced because this magnetic field has no vertical ‘component’.

Edited by MitkoGorgiev, 02 February 2020 - 04:04 AM.

Also tagged with one or more of these keywords: electromagnetism, electric current, induction, electrical engineering, physics