Practice question

**Effect of dielectric** is to reduce effective field due to polarization, bound surface charges opposite to free charges, net field E = E₀ - E_p = E₀/K. Capacitance C = Q/V = K ε₀ A/d for full filling, partial filling C = ε₀ A/(d - t + t/K) for slab thickness t. With a constant voltage V across the plates, the electric field E varies between regions. In the air region, Eₐir = (V/d) , where d is the plate separation. In the dielectric region ( K > 1 ), polarization reduces the field: Ediₑlₑctric = (Eₐir/K) = (V/K d) . Since K > 1