Question
A certain wire $\mathrm{A}$ has resistance $81 ~\Omega$. The resistance of another wire $\mathrm{B}$ of same material and equal length but of diameter thrice the diameter of A will be :
A certain wire $\mathrm{A}$ has resistance $81 ~\Omega$. The resistance of another wire $\mathrm{B}$ of same material and equal length but of diameter thrice the diameter of A will be :