A long round conductor of cross-sectional area S is made of material whose resistivity depends only on a distance r from the axis of the conductor as rho=alpha//r^(2), where alpha is a constant. Find the total resistance per unit length of the rod when potential difference is applied across its length.

A long round conductor of cross-sectional area S is made of material w

1.	A long round conductor of cross-sectional area S is made of material whose resistivity depends only on a distance r from the axis of the conductor as rho=alpha//r^(2), where alpha is a constant. Find the total resistance per unit length of the rod when potential difference is applied across its length.
Answer» `(PI alpha)/(S^(2))` `(2pialpha)/(S^(2))` `(pi alpha)/(2S^(2))` `(alpha)/(S^(2))` ANSWER :B

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