Two identical capacitors are connected in the circuit shown. `C_(2)` is charged to `100 V` and switch `S` is shifted from position `1` to position `2`. The negative terminal of `C_(2)` is connected with the positive terminal of `C_(1)`. Find the work done by the battery. If the polarity of `C_(2)` were reversed, what work would have been done by the battery ?

Explanation

Case I :-
`KVLrArr100-(2(1000+q))/(C )=0`
`Q=500muC`
Work done by the battery, `W=0.5xx10^(-3)xx100=0.05J`
Case II :-
`KVL`
`rArr 100-(((q-1000))/(10))-(((q+1000))/(10))=0`
`Q=500muC`
`:. ` Work done by the battery, `W=DeltaqE=0.05J`