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receive electricity.
2. Ask your fellow-student about history of electricity and
magnetism.

LESSON 2

OERSTED AND FARADAY

Starter: Electricity and magnetism are closely linked. In what way?
Input: Oersted’s Experiment

In the winter of 1819-20 Christian Oersted was doing
experiments to find links between electricity, magnetism, light and
heat. One of these experiments was very important, as it was the
first step towards the invention of the generator or dynamo.
Oersted’s apparatus was very simple. He took a piece of wire
and bent it to make a kind of bridge. Leads to the terminals of an

electric battery could connect the ends of the wire. The only other
piece of equipment was a pivoted magnet, like a compass needle.
It had long been known that magnets have two poles - north
and south. Unlike poles attract and like poles repel. Oersted also
knew that there was a relationship between electricity and
magnetism and he showed this by placing the magnetic needle
below the wire, then connecting the wire to the battery. The needle
was deflecting by the current in the wire. The wire was acting like
another magnet and influencing the magnetic needle below it.
What made the experiment so important was the next stage: when
he placed the needle above the wire the needle was again
deflected, but this time in the opposite direction.
Oersted concluded that there must be some sort of circular power
or force around the wire. This force made the magnet move in
opposite directions depending on its position relative to the
electrically charged wire.

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