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प्रश्न
The electric bulbs used these days have a coil-coiled filament. State its reason.
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उत्तर
On account of having a coil-coiled filament, the area of spread of tungsten is much and so the heat now produced in a very small area, raises the temperatures to a high degree i.e., 2300°C, producting more bright light.
संबंधित प्रश्न
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