How to Derive Electrostatic Boundary Conditions for Polarisation Field P?

[dsta]

Homework Statement

Use a Gaussian surface and an Amperian loop to derive the electrostatic boundary conditions for the polarisation field P at an interface between electric media 1 and 2 of relative permittivities e1 and e2. (Hint: determine results for D and E first)

Homework Equations

The Attempt at a Solution

The boundary conditions for E and D I know. I know that the restrictions on P will have something to do with the bound charge at the interface, and I know that $$P = D - \epsilon_{o}E$$. I am not sure what Gaussian surface or Amperian loop I should use, and how I should use it.

 

[manyparticle]

$$\int D \cdot ds=4\pi \rho$$