Given figure shows steady flow of current in a metallic conductor of non uniform cross - section. Current density depends inversely upon the area, so, J₁> J₂ as A₁ < A₂ 

A steady current flows in a metallic conductor of non uniform cross section. Which of the following quantities is constant along the conductor?

Current

When steady current flows through a metallic conductor of non-uniform cross-section, the current flowing through the conductor is constant. Current does not depend on the area of the conductor, hence it remains a constant. However, current density, electric field, and drift speed are inversely proportional to the area of cross-section.