$ = {\rm{Q}}\left( {{{\rm{E}}_1}\widehat {\rm{i}} + {{\rm{E}}_2}\widehat {\rm{j}}} \right) \cdot ({\rm{a}}\widehat {\rm{i}} + {\rm{b}}\widehat {\rm{j}}) = {\rm{Q}}\left( {{{\rm{E}}_1}{\rm{a}} + {{\rm{E}}_2}{\rm{b}}} \right)$


Reason $(R):$ A spherical equipotential surface is possible inside a spherical capacitor.

