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प्रश्न
Give a scientific reason.
Tungsten metal is used to make a solenoid type coil in an electric bulb.
उत्तर
- The electric bulb works on the principle of the heating effect of electric current.
- The solenoid-type coil of the bulb has high resistivity and a very high melting point.
- When current is passed through the bulb, the solenoid-type coil of the bulb gets heated to a high temperature (up to 3400°C) and starts glowing.
Hence, tungsten metal makes a solenoid-type coil in an electric bulb.
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