Question

The resistance of a conductor of length x is r. If its area of crosssection is a, what is its resistivity? What is its unit?

Answer 1

ohm per metre is the unit .

Answer 2

Answer:

Resitivity of the material is  $\rho = \frac{ra}{x}$

The S.I units of resistivity is ohm metre.

Explanation:

We know that resistance of the conductor depends upon

(1) length of the conductor

(2)Area of the cross-section of the conductor

$r \alpha \frac{x}{a}$

where $\alpha$ is the sign of proportionality.

after removing the sign of proportionality, we get,

$r = \rho\frac{x}{a}$ ................(1)

where $\rho$ = resitivity of the material

So, $\rho = \frac{ra}{x}$

The S.I units of resistivity is ohm metre.