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I have a question about this, the magnetic field is the solenoid coil, and its magnetic field generates an electric field, when a load (like a magnet) modifies the magnetic field of the solenoid coil. But I also read that it is the magnet that has the magnetic field, and that when you insert it into the solenoid, an electric field is created, does the magnet field change? It is only a question related to the real functioning of induction, since I have been investigating for many hours, without a concrete answer, so

How really works the induction electromagnetic, without very scientific terms.

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A solenoid which carries a constant current creates a magnetic field. It only generates an electric field if the current is changing. This induced electric field is not the same as the applied electric field which is required to make a current flow in the wires of the solenoid.

A stationary magnet (eg a bar magnet) also generates a magnetic field. The magnetic fields of the solenoid (carrying a constant current) and the stationary bar magnet add up as vectors.

You seem to be complicating the situation by plunging a moving bar magnet into a solenoid which is already carrying an electric current. Textbooks usually describe the solenoid without a current when the bar magnet is plunged into it. The bar magnet then induces an emf in the solenoid, which causes a current to flow in the solenoid, and the current in the solenoid then creates a magnetic field which opposes that of the bar magnet.

During this experiment the magnetic field of the bar magnet does not change, but the magnetic field of the solenoid does change.

Induced electric field in circular wire around solenoid
How is the electric field near a solenoid?
What is the electric field outside a cylindrical solenoid?

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  • $\begingroup$ One doubt I have is, is the solenoid a magnetic field by itself? Is it enough that you wind wire to a cylindrical wire and I will have a magnetic field formed? $\endgroup$
    – ESCM
    Commented Oct 3, 2017 at 20:53
  • $\begingroup$ Or when the magnet enters the solenoid, does the solenoid just create a magnetic field? $\endgroup$
    – ESCM
    Commented Oct 3, 2017 at 20:54
  • $\begingroup$ Also you say that they are added as vectors, but then you tell me that the magnetic fields are opposing, so how can they be added? $\endgroup$
    – ESCM
    Commented Oct 3, 2017 at 20:55
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All Electromagnetic phenomenon are produced by charges and currents. Even though the curl of the electric field is equal to the negative time derivative of the magnetic field$\nabla \times \vec{E}=-\partial\vec{B}/\partial t$, , thus giving rise to Magnetic Induction, both of these effects are due to some past orientation of current and charge. To find the actual cause of this relationship, it's probably best to look at the Jefimenko's Equations. These describe the time dependent fields in terms of time dependent charge and current distributions.

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A solenoid is nothing but a coiled wire. When current flows through it , magnetic field is generated due to the moving charges.

Note that an electric field only comes into play when there is a time varying magnetic field.

Moreover, this electric field is different from the field generated by static charges since this field forms closed loops and is hence Non-Conservative in nature.

Inserting a bar magnet will only change the flux passing through the loops of the solenoid which will thereby cause an induced EMF to be generated. Electric field is NOT generated by inserting the bar magnet since it's magnetic field is constant.

So what exactly is happening? Simple.

As mentioned by Sammy in his answer, the induced EMF due to the barmagnet cause an electric current to flow in a direction such that the magnetic field generated by THIS current opposes the field generated by the current in the solenoid.

This "opposite current" is what is called 'Induced Current' and this principle is called Electromagnetic Induction.

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