Ah, I see... I was basically only converting one "side" of the square. Guess my intuition was more correct than I gave it credit for.
Thanks--fixing this gave me the correct result. Glad I wasn't misunderstanding the general concept.
Homework Statement
Two parallel plates are connected to a battery which maintains a constant potential difference of 12.0 V. The distance between the plates can be varied and there are three plates of different dielectric materials available: rubber (0.40 mm, κ = 6.7), glass (4 mm, κ = 7) and...