What Is Resistivity where ρ (rho) is called resistivity of the material of conductor. If, l = 1 m and a = 1 m2 Then R = ρ .... (ii) Thus, if we take 1 metre long piece of a substance having a cross-sectional area of 1 meter2, then the resistance of that piece of the substance is called its resistivity. Resistivity of a substance can … [Read more...] about What Is Resistivity