Question
Why are alloys used for making standard resistance coils?
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Answer
Alloys are used for making standard resistance coil because they have low temperature coefficient of resistance with less temperature sensitivity.
This keeps the resistance of the wire almost constant even in small temperature change. The alloys also have high resistivity and hence high resistance, because for given length and cross-section area of conductor (L and A are constant).
$\text{R}\hat{\text{I}}\pm\text{p}$
This keeps the resistance of the wire almost constant even in small temperature change. The alloys also have high resistivity and hence high resistance, because for given length and cross-section area of conductor (L and A are constant).
$\text{R}\hat{\text{I}}\pm\text{p}$
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