The insulated spheres of radii R1 and R2 having charges Q1 , and Q2, respectively, are connected to each other. There is
No change in the energy of the system
An increase in the energy of the system
Always a decrease in the energy of the system
A decrease in the energy of the system until Q1R2 = Q2R1
When Q1R1≠Q2R2 current will flow in connecting wire so that energy decreases in the form of heat through the connecting wire.