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प्रश्न
What is a permanent magnet? Give one use of it.
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उत्तर
A permanent magnet is a magnet made from steel such that once magnetized, it does not lose its magnetism easily. Use: It is used in the galvanometer.
संबंधित प्रश्न
The diagram shows a coil wound around a U shape soft iron bar AB.
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How does a magnetic field set up by a solenoid change when cross-sectional area of solenoid is increased?
