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प्रश्न
State the factors on which the strength of an electromagnet depends. How does it depend on these factors?
Explain the factors on which the strength of an electromagnet depends.
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उत्तर
Strength of an electromagnet depends on the following factors:
- Number of turns in the coil: By increasing the number of turns in the coil, the strength of the electromagnet can be increased.
- Current flowing through the coil: By increasing the flow of current in the coil, the strength of the electromagnet can be increased.
- Length of air gaps between poles: By reducing the length of air gaps between the poles, the strength of the electromagnet can be increased.
संबंधित प्रश्न
It is desired to measure the magnitude of field between the poles of a powerful loud speaker magnet. A small flat search coil of area 2 cm2 with 25 closely wound turns, is positioned normal to the field direction, and then quickly snatched out of the field region. Equivalently, one can give it a quick 90° turn to bring its plane parallel to the field direction. The total charge flown in the coil (measured by a ballistic galvanometer connected to coil) is 7.5 mC. The combined resistance of the coil and the galvanometer is 0.50 Ω. Estimate the field strength of magnet.
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