When Dielectric is Partial Filled between the Plates #8211; If a dielectric slab of thickness t(t lt; d) is inserted between the plates as shown. Then, E = Electric field between the plates, E<sub>i</sub> = Induced electric field in direction. E = (E #8211; E<sub>i</sub>), the reduced value of electric field in the dielectric. i.e. C = Q/V ⇒ C = ε<sub>0</sub>A/(d #8211; t) + 1/K