image by explainthatstuff
We’re finishing off the electricity unit by looking at electric motors. The page I used in class to help explain how a simple electric motor works is available here.
Here is another nice animation that shows the key parts of an electric motor. It will stop after a few rotations but just reload the page to see it again.
Real electric motors have a few modifications;
- they use field coils instead of a bar magnet – the field coils form a strong electromagnet when current passes through them. The field coils do not rotate.
- the single rotating coil is replaced by several rotating coils
- there are more contacts on the commutator – each pair connects to a different rotating coil
- the brushes are often made from carbon instead of metal – the carbon conducts electricity and can withstand high temperatures. Carbon also moulds to the shape of the commutator to give a good electrical contact
image by marrrci