Class 12 NEET Physics Current Electricity Questions Part 1

Resistance of a conductor is given by R=ρ

l

A

, where ρ is the specific resistance, l is the length and A is the cross-sectional area of the conductor.
Now, when l=1 and A=1,R=ρ
So specific resistance or resistivity of a material may be defined as the resistance of a specimen of the material having unit length and unit cross-section. Hence, specific resistance is a property of a material and it will increase with the increase of temperature, but will not vary with the dimensions (length, cross-section) of the conductor.