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Question
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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Solution
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.
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