Given, a parallel plate capacitor is charged to a potential difference V. If the distance between the plates is doubled then,i) Electric field in between the plates is given by E=σε∘Since, E does not depend upon distance between the capacitor plates, electric field remains unaffected.ii) Capacitance is given by C=ε∘AdWhen distance between the plates is doubled C =ε∘A2d=12C That is, capacitance becomes half of it s initial value.iii) Energy is given by U=12Q2CThere is no change in Q but, capacitance changes. Since Capacitance becomes half, stored energy of the capacitor becomes twice of it s initial value. [Capacitance and energy have inverse dependance].