Several experiments in order to understand what is electromagnetic induction. Electromagnetic induction is the generation of electric current in an electrical conductor when it is passed through a variable magnetic field.

The more turns of wire the more voltage induced.

If we connect a small DC electrical motor to the coil we will se how the axle is moved some degrees to the left or to the right as we move the magnet inside the coil.

Small demonstration of how some mechanical flashlights work. Connect a LED (Light Emitting Diode) to the coil. We will se that in this case the LED only is turned on the the magnet moves in one direction, because LEDs have polarity and don't work with inverted polarity.

https://en.wikipedia.org/wiki/Electro...
https://en.wikipedia.org/wiki/Faraday...
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