Page 47 - Innovator's Science-8

• Connect the second wire between the cell holder and the switch
• Place the magne c compass beneath the wire between the two nails.
When you turn the switch to the ON posi on, electric current starts flowing through
the wire, You will no ce that the compass needle moves or gets deflected from its
usual direc on. This happens because the electric current in the wire creates an
invisible force around it called a magne c field, which acts on the magne c needle
of the compass. When you turn the switch OFF and the current stops flowing, the
magne c field disappears, and the compass needle goes back to poin ng in its
original direc on. So, the movement of the compass needle shows that an electric
current can produce a magne c effect around the wire.

Conclusion: When electric current flows through a conductor (like a wire), it produces
a magne c field around it. This phenomenon is known as the magne c effect of
electric current. The magne c field disappears when the current stops flowing.
Science
Bytes

Testimony
You have just now made the same discovery which was made by the scien st Hans Chris an Oersted (1777–1851) in 1820, that is, that
electricity and magne sm are linked. He was a professor at a university in Denmark. It is said that once while giving a demonstra on,
he no ced that whenever an electrical circuit was closed or opened, the needle of a magne c compass, lying nearby, deflected. He
inves gated this and when he was certain that an electric current indeed produced a magne c field, he published his findings. This led
to other scien sts repea ng his experiment to check if they got the same results, and further inves ga ng the connec on between
electricity and magne sm.
The magne c effect of electric current has many prac cal applica ons, such as in devices like electromagnets, electric bells, motors,
fans, loudspeakers, and more.

ELECTROMAGNETS
This experiment shows how electricity can create a temporary magnet. You
wrap a wire around an iron nail and connect it to a battery. When the

electric current flows through the wire, it turns the nail into a magnet,
making it able to attract and hold iron paper clips. Once you disconnect the
wire and stop the current, the nail loses its magnetism, and the paper clips

fall off. This type of temporary magnet is called an electromagnet.
Coil of wire
connected with Let us now try to investigate these observations in detail through the next
a cell
activity.

Activity-2 Aim: To demonstrate that electricity can be used to create a temporary magnet,
called an electromagnet.
Experiential Learning
Materials Required: A 100 cm long flexible insulated wire, a piece of chart paper, an
iron nail, an electric cell, two magne c compasses, and few iron/steel paper clips.
Procedure:

• Roll a piece of chart paper to make a cylinder of diameter roughly equal to the
width of a pencil. Secure it with an adhesive tape.

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Science-8