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प्रश्न
Why does the cord of an electric heater not glow while the heating element does?
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उत्तर
The heating element of the heater is made up of alloy which has very high resistance so when current flows through the heating element, it becomes too hot and glows red. But the resistance of cord which is usually of copper or aluminium is very low so it does not glow.
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संबंधित प्रश्न
Write Joule's law of heating.
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(a) magnitude of resistance of the resistor
(b) temperature of the resistor
(c) magnitude of current
(d) time for which current is passed
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(a) tungsten
(b) bronze
(c) nichrome
(d) argon
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