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प्रश्न
Write the answer in your word.
How is an electromagnet made?
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उत्तर
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
संबंधित प्रश्न
You are given an iron nail, a torch cell, and a long piece of insulated copper wire. With the help of a labelled neat diagram, describe in steps how you will make the nail, an electromagnet.
Name the material used for making the armature of an electric bell. Give a reason for your answer.
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Fill in the blanks by writing (i) Only soft iron, (ii) Only steel, (iii) Both soft-iron and steel for the material of core and/or magnet.
Electric bell ______.
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Answer the following in short.
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State the energy change that takes’place in a D. C. motor.
State the principle of a D. C. motor.
The primary windings of a step-up transformer are usually made of thicker wire than the secondary. Explain.
