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प्रश्न
Why are the conductors of electric heating devices, such as bread-toasters and electric irons, made of an alloy rather than a pure metal?
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उत्तर
The conductors of electric heating devices, such as bread toasters and electric irons, are made of alloy instead of pure metal for the following reasons:
- The resistivity of an alloy is higher than that of a metal, which produces a large amount of heat.
- Oxidation of alloys does not occur quickly at high temperatures.
- There is a negligible change in their resistance with an increase in temperature.
संबंधित प्रश्न
Why is the tungsten used almost exclusively for filament of electric lamps?
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(c) magnitude of current
(d) time for which current is passed
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She wrote: Three-pin connections reduce heating of connecting wires.
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