1. The problem statement, all variables and given/known data The plates of a parallel plate capacitor of capacitance C0 are horizontal. Into the gap a slab of dielectric material with K=2 is placed, filling the bottom half of the gap between the plates. What is the resulting new capacitance? 2. Relevant equations C = Q/V = κɛ0A/d 3. The attempt at a solution Co = ɛ0A/d Cf = kɛ0A/d = ((ɛ0)(0.5A)/d) + ((2ɛ0)(1/2a)/(d)) = (ɛ0A/2d) +(ɛ0A/d) = (ɛ0A/d) + (2ɛ0A/2d) = (3ɛ0A/2d) Cf = 3/2 Co The correct answer is 4/3 Co. Guys, can anyone help me out? I have no idea how to derive the correct answer.