Question

Alloy of metal have greater resistivity than their constituent metal? why

Answer 1

In the case of alloys the ions of one material is randomly attached to another ion/ atom of the other material. there is no defenite crystal lattice like structure. Hence conduction be tough and thus they have high resistivity.

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Answer 2

Alloy of metal have greater resistivity than their constituent metal because alloy have better properties than that of metal.Alloys usually have temperature coefficients of resistance than pure metal as well as the resistivity of the alloy manganin is nearly independent/increase rapidly with increase of temperature.
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