1. The problem statement, all variables and given/known data The gap between a pair of parallel infinite copper plates extends from z = 0 to z = W > 0 and is originally occupied by vacuum (ε0, μ0). The plates carry equal and oppositely signed surface charge densities and as a consequence we have a constant electric field E = −4ˆz V/m in vacuum in the gap region. What would be the new equilibrium values of E, D, and P in the gap region if some amount of salt were dissolved in the fluid in the gap (64ε0) to raise its conductivity to σ = 4 S/m (conductivity of sea water)? State the values of E, D, and P after a steady-state equilibrium is reached and briey explain your answer. 2. Relevant equations D=εE=ε0*E0+P P=polarization vector 3. The attempt at a solution I have the equation J = σE, but I do not know how to relate this to D and P, since I am not given J in the problem Thanks!!!