What is conductivity? On which factors does its value depend? Write its unit and dimension.
(N/A) Conductivity is defined as the reciprocal of resistivity. It is denoted by the symbol $\sigma$.
$\sigma = \frac{1}{\rho} = \frac{l}{RA}$
The $SI$ unit of conductivity is $\Omega^{-1} m^{-1}$ or $S m^{-1}$ (Siemens per meter).
The dimensional formula of conductivity is $[M^{-1} L^{-3} T^{3} A^{2}]$.
The value of conductivity depends on the nature of the material,temperature,and pressure.
It does not depend on the physical dimensions (length or cross-sectional area) of the conductor.
$\sigma = \frac{1}{\rho} = \frac{l}{RA}$
The $SI$ unit of conductivity is $\Omega^{-1} m^{-1}$ or $S m^{-1}$ (Siemens per meter).
The dimensional formula of conductivity is $[M^{-1} L^{-3} T^{3} A^{2}]$.
The value of conductivity depends on the nature of the material,temperature,and pressure.
It does not depend on the physical dimensions (length or cross-sectional area) of the conductor.
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