State some uses of electromagnets.
- Maglev trains
- X-Ray machines
- Starting a car engine.
- Scrapyards - lifting cars
- Motors in microwaves (to turn plate)
How are magnets used in maglev trains?
Magnets on the train and tracks repel each other so the train 'hovers' so there is no friction between the train and the tracks.
Magnets repel the train forwards so no engine is needed.
Why are electromagnets used in x-ray machines?
They are used in the 'relay' switch that switches the machine on and off safely.
What is a relay?
A relay is a magnetic switch that is activated by a small current.
This then switches on a bigger circuit with a much larger current.
Relays make circuits with large currents safe.