Two plates of parallel plates capacitor are charge plate +2Q and -Q.find the potential of Capacitance of Capacitor of Capacitor.the distance between plates should be taken d and the area of the plate A.

 

E1 and E4 will be cancelled,so +Q/2(1) and+Q/2(4)will be useless.

charge of capacitor +3Q/2

V=E.d

V=(E2+E3).d