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Hans Christian Oersted had done more
than discover
electromagnetism
.
Much more. He’d given scientists the
ability to create a powerful new tool—
the
electromagnet
.
Why are electromagnets so much
more useful than regular magnets?
Because they can be turned on and off.
That’s right! A quick flip of a switch
starts or stops the flow of electricity.
By 1832, American scientist
Joseph Henry had built an electromagnet strong enough to
lift 3,600 pounds (1,633 kilograms). That’s about the weight
of a small car.
Today electromagnets are used in everything from
doorbells and electric guitars to junkyard cranes and high-
speed trains. Life just wouldn’t be the same without them.
Easy On,
Easy Off
