A copper disc and a carbon disc of same radius are assembled alternately and co-axially to make a cylindrical conductor whose temperature coefficient conductor whose temperature coefficient of resistance is almost equal to zero. Ratio of thickness of the copper and the carbon disc is (neglect change in length. `alpha_(CU)` and `-alpha_(C)` represent the temperature coefficients of resistivities and `p_(cu)` carbon at room temperature respectively)A. `p_(C)alpha_(C)//p_(CU)alpha_(CU)`B. `p_(CU)alpha_(CU)//p_(C)alpha_(C)`C. `p_(C)alpha_(CU)//p_(CU)alpha_(C)`D. `p_(CU)alpha_(C)//p_(C)alpha_(CU)`

A copper disc and a carbon disc of same radius are assembled alternate

1.	A copper disc and a carbon disc of same radius are assembled alternately and co-axially to make a cylindrical conductor whose temperature coefficient conductor whose temperature coefficient of resistance is almost equal to zero. Ratio of thickness of the copper and the carbon disc is (neglect change in length. `alpha_(CU)` and `-alpha_(C)` represent the temperature coefficients of resistivities and `p_(cu)` carbon at room temperature respectively)A. `p_(C)alpha_(C)//p_(CU)alpha_(CU)`B. `p_(CU)alpha_(CU)//p_(C)alpha_(C)`C. `p_(C)alpha_(CU)//p_(CU)alpha_(C)`D. `p_(CU)alpha_(C)//p_(C)alpha_(CU)`
Answer» Correct Answer - A

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