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प्रश्न
How will you make an iron bar electromagnet? Draw a diagram showing the polarities of the electromagnet?
उत्तर
Take the given iron bar AB. Wound several turns of insulated copper wire over the bar. Connect the ends of the wire to a battery through a switch. Press the switch to pass current. After some time, the bar AB becomes a magnet.
The end A of the bar at which the current enters the coil in clock¬wise direction becomes the south pole (S) and the end B of the bar at which the current leaves the coil in anti-clockwise direc¬tion becomes the north pole (N).
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संबंधित प्रश्न
The diagram shows a coil wound around a U shape soft iron bar AB.
1) What is the polarity induced at the ends A and B when the switch is pressed?
2) Suggest one way to strengthen the magnetic field in the electromagnet
3) What will be the polarities at A & B if the direction of current is reversed in the circuit?
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