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प्रश्न
In an electric bulb, coil of _______ metal is used.
विकल्प
copper
tungsten
aluminium
iron
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उत्तर
In an electric bulb, coil of tungsten metal is used.
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संबंधित प्रश्न
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How does the resistance of a wire vary with its area of cross-section?
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Give two reasons why nichrome alloy is used for making the heating elements of electrical appliances.
Why does the connecting cord of an electric heater not glow hot while the heating element does?
Explain why, tungsten is used for making the filaments of electric bulbs.
Name the material which is used for making the filaments of an electric bulb.
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(a) thin and short
(b) thick and short
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what is the heating effect of the electric current? state any four applications of it?
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SFEU
Your teacher has shown you the following activity.
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Write down any three questions that come to your mind about this activity.
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She wrote: Three-pin connections reduce heating of connecting wires.
- Is her answer correct or incorrect? Justify.
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