Two identical capacitors, have the same capacitance C. One of them is charged to potential `V_1` and the other `V_2`. The negative ends of the capacitors are connected together. When the poistive ends are also connected, the decrease in energy of the combined system is

Options

A. `1//4C(V_(1)^(2)-V_(2)^(2))`
B. `1//4C(V_(1)^(2)+V_(2)^(2))`
C. `1//4C(V_(1)-V_(2))^(2)`
D. `1//4C (V_(1)+V_(2))^(2)`

Answer

C

Explanation

`Q=CV, U_(i)=1//2CV^(2)`
`U_(f)=1//2CV^(2)` work done `=U_(i)-U_(f)`