A cylindrical metal wire of length $l$ and cross sections area $S$, has resistance $R$, conductance $G$, conductivity $\sigma$ and resistivity $\rho$. Which one of the following expressions for $\sigma$ is valid
  • A$\frac{{GR}}{\rho }$
  • B$\frac{{\rho R}}{G}$
  • C$\frac{{GS}}{l}$
  • D$\frac{{Rl}}{S}$
Medium
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