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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?
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 metal, which produces a large amount of heat.
- Oxidation of alloys does not occur quickly at high temperatures.
- There is negligible change in their resistance with increase in temperature.
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