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प्रश्न
You are required to make an electromagnet from a soft iron bar by using a cell, an insulated coil of copper wire and a switch. (a) Draw a circuit diagram to represent the process. (b) label the poles of the electromagnet.
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उत्तर
संबंधित प्रश्न
State the principle on which transformer works.
What type of current is transmitted from the power station?
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Mention two main sources of power loss in real transformers.
