Question: How does an electric motor work?

John Welford answered on 25 Jun 2012:

Hi eeewan. There are lots of different types of electric motors that all work in a slightly differently. The one thing they all have in common is that they convert electrical energy (voltage and current) into movement (or “Kinetic” energy).

Most motors do this by using electromagnetism. You have probably played with magnets and made them attract or repel each other. You might have also done experiments where you make “electromagnets” out of coils of wire. These behave like magnets when current is flowing in the wire, but stop being magnetic when the current is turned off. Perhaps you have used them to pick up paperclips or something similar? If you haven’t done this then maybe ask your teacher, it is a really simple experiment to do and you will learn a lot about electricity and magnets!

Next if you imagine a line of electromagnets close to one another and a paperclip at one end, switching the the magnets on and off in order should make the paperclip move along the line of magnets. That is really all an electric motor is doing – switching on and off electromagnets to make something move.

Usually they are arranged so that the movement is turning something on an axle, and the switching is done automatically. Sometimes it is just metal that is attracted to an electromagnet, sometimes it is two electromagnets, or one side can be a permanent magnet. There are lots of different combinations.

I hope that helps answer your question. Let me know if you have any more questions about motors!