Choose the correct alternative: (a) Alloys of metals usually have (greater/less) resistivity than that of their consituent metals. (b) Alloys usually have much (lower/higher) temperature coefficients of resistance than pure metals. The resistivity of the alloy manganin is nearly independent of/increases rapidly with increase of temperature. The resistivity of a typical insulator (e.g., amber) is greater than that of a metal by a factor of the order (10^(22) // 10^(23)).

Choose the correct alternative: (a) Alloys of metals usually have (gr

1.	Choose the correct alternative: (a) Alloys of metals usually have (greater/less) resistivity than that of their consituent metals. (b) Alloys usually have much (lower/higher) temperature coefficients of resistance than pure metals. The resistivity of the alloy manganin is nearly independent of/increases rapidly with increase of temperature. The resistivity of a typical insulator (e.g., amber) is greater than that of a metal by a factor of the order (10^(22) // 10^(23)).
Answer» Solution :(a) GREATER (b) Lower (C ) Nearly independent `10^(22)`

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