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Magnetism

Magnets are materials that naturally attract iron, nickel, and
cobalt. Around 1600,an English physician, William Gilbert, wrote
that the earth is one big round magnet and that its poles are
magnetically charged. Gilbert demonstrated this with a compass. A
compass has a magnetized needle, one end of which points
approximately to the earth’s north pole. Gilbert was the first to use
the term magnetic pole.
It wasn’t until 1820 that a Danish scientist, Hans Christian
Oersted, noticed that an electrical current flowing through a
conductor acted like a magnet. Oersted demonstrated the
connection between magnetism and electricity. About the same
time, a Frenchman, Andre Ampere, developed the mathematical
theories that described electrical currents and magnets.
English physicist Michael Faraday discovered that a
magnat moving in a coil of wire acts as a generator. In other
words, magnets can create an electric current. Current is measured
by a machine called a galvanometer.

Comprehension Questions

I. Say which of the following statements are false and
which are true. Correct the false statements to make them
true.

1. Magnets cannot attract iron, nickel and cobalt.
2. A compass has a magnetized needle.

3. The term magnetic pole was first used by Gilbert.

4. Magnets cannot create an electric current.
5. Galvanometer measures current.

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