A parallel plate capacitor is shown in Fig. It is made of two square metal plates of $$400$$ $$mm$$ side. The $$14$$ $$mm$$ space between the plates is filled with two layers of dielectrics of $${\varepsilon _r} = 4,6\,\,mm$$ thick and $${\varepsilon _r} = 2,8\,\,mm$$ thick. Neglecting fringing of fields at the edges, the capacitance is

Given a vector field $$\overrightarrow F ,$$ the divergence theorem states that

In a uniform electric field, field lines and equipotentials

If v, w, q stand for voltage, energy and charge, then v can be expressed