question_answer 19)

Choose the correct alternative: (a) Alloys of metals usually have Greater less) resistivity than that of their constituent metals. (b) Alloys usually have much (lower/higher) temperature co-efficients of resistance than pure metals. (c) The resistivity of the alloy manganin is nearly independent of/increases rapidly with increase of temperature. (d) The resistivity of a typical insulator (e.g., amber) is greater than that of a metal by a factor of the order of (1022/103).  

Answer:

(a) Greater (b) Lower (c) Nearly independent (d) 1022.