Question

What is the SI unit of electrical resistivity of a material ?

• A. $\Omega .cm$
• B. $\Omega .m$
• C. $\Omega .c{m}^2$
• D. $\Omega .m^2$

Answer 1

The correct option is B $\Omega .m$

The resistivity is given by,

$\rho =\frac{RA}{l}$

As the resistance has a unit of $\Omega$ , length has the unit of $m$ and unit of area is $m^2$,

so,

$\rho$ has a unit of $\Omega -m$