A large brass washer has a 2-cm inside diameter, a 5-cm outside diameter, and is 0.5 cm thick. Its conductivity is σ = 1.5 × 10⁷ S/m. The washer is cut in half along a diameter, and a voltage is applied between the two rectangular faces of one part. The resultant electric field in the interior of the half-washer is E = (0.5/ρ) a_ϕ V/m in cylindrical coordinates, where the z axis is the axis of the washer.

(a) What potential difference exists between the two rectangular faces?

(b) What total current is flowing?

(c) What is the resistance between the two faces?