A wire with conductivity carries current I. The current is increasing at the rate dI/dt. a.

A wire with conductivity σ carries current I. The current is increasing at the rate dI/dt.
a. Show that there is a displacement current in the wire equal to (є₀/σ)(dI/dt).
b. Evaluate the displacement current for a copper wire in which the current is increasing at 1.0 × 10⁶ A/s.