Chapter 3

Electromagnetic induction

Power of the induced electromotive force and the Laplace's force

Fondamental

A charge carrier is put in a permanent magnetic field.

It moves with a velocity in relation to the conductor, but the conductor moves at velocity in the laboratory referential .

Power

In this referential, the charge carrier has a speed ( ) and is subject to Lorentz's Force :

Yet its power is equal to zero :

This power can be separated in 4 terms, and two of them are equal to zero :

In an elementary volume , the number of charge carriers is .

The density of power of Lorentz's force is :

The term :

represents the density of power of the force applied to the charges because of the electromotive field .

This density is evaluated in the referential of the conductor.

By adding it on the whole volume of the conductor, the power of the induced electromotive force is found :

Interpretation of the term   :

This term appears to be the power of Laplace's force applied to elementary volume  .

Finally, after integration :

The power of the induction electromotive force is compensated by that of the actions of the Laplace's force on the circuit.

AttentionPower of induced electromotive force and Laplace's force

The power of the induction electromotive force is compensated by that of the actions of the Laplace force on the circuit.

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