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An electromagnet is very beneficial because it can be 14 on and off easily (using an electric current), whereas a 15 magnet cannot be turned 16 and will continue to affect its immediate environment.
Iron stops being an electromagnet very quickly, but 17 takes time to wear off.
To make an electromagnet, 18 wire is 19 around a steel 20 . The two ends of the wire are 21 to the + (positive) and - (negative) side of the 22 .
Electromagnets are used in everyday items such as 23 alarms, electric relays and 24 bells.
Electric 25 are basically electromagnets. Their ability to change from the state of
26 to magnetic just by passing an electric current through it allows it to be used in many different items. This ability is used in relays.
Electromagnets can also be used to make electricity. 27 of a magnet back and forth in front of the electromagnet will make an 28 current.