We know that a soft iron bar placed inside a solenoid turns into an electromagnet when current passes through the solenoid. Now my question is how is electricity produced? Is the iron core moved by the turbine inside a solenoid?

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quillassed7 · Accepted Answer

This it because it produces a changing magnetic field. And Maxwell&#039;s equations (Faraday&#039;s law) teaches us that a changing magnetic field results in an electric field, which gives rise to a current in a nearby wire. It&#039;s not the magnetic field providing the force, it&#039;s the electric field generated by the changing magnetic field. (The current disappears when you stop moving the magnet with respect to the solenoid, i.e. when the magnetic field stops changing)With the coil stationary and the magnet moving, we have to perform a Lorentz transformation (a change in coordinates that occurs when we switch velocities, used in special relativity). Under such a transformation, a moving magnetic field becomes a stationary magnetic field plus an electric field.In this case the magnetic field doesn&#039;t change direction, but an electric field is produced and it is this field that causes the electrons to move.A full understanding of the dynamics of electric and magnetic fields can&#039;t work without including special relativity which is why, usually, the question of current induction is explained in terms of Faraday&#039;s Law, which is yet another perspective on the scenario.

We know that a soft iron bar placed inside a solenoid turns into an electromagnet when current passes through the solenoid. Now my question is how is electricity produced? Is the iron core moved by the turbine inside a solenoid?

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