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Question
Write the answer in your words.
How is an electromagnet made?
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Solution
For the construction of an electromagnet, we require an iron nail, a long insulated copper wire, a battery and a switch.
The long, insulated copper wire is first wound on the iron nail. Then the two free ends of the wire are connected to the battery and the switch as shown. Now that the switch is turned on, current flows through the circuit. Due to this flow of current, the insulated copper wire and iron nail act as an electromagnet. Now, if iron pins are brought close to this set-up, they stick to the iron nail.
As soon as the current stops flowing in the circuit, the iron nail loses magnetism and the pins fall off.
Case: Switch open
Case: Switch close
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