Net capacitance of three identical capacitors in series is `1muF`. What will be their net capacitance if connected in parallel?
Find the ratio of energy stored in the two configurations if they are both connected to the same source.

Explanation

Let C be the capacitance of each capacitor, then in series `(1)/(C_(S))=(1)/(C)+(1)/(C)+(1)/(C)=(3)/(C)`.
or `C=3C_(S)=3xx1muF=3muF`
When these capacitors are connected in parallel net capacitance, `C_(P)=3C=3xx3=9muF`
when these two combinations are connected to same source the potential difference across each combination is same.
Ratio of energy stored, `(U_(S))/(U_(p))=((1)/(2)C_(S)V^(2))/((1)/(2)C_(p)V^(2))=(C_(S))/(C_(p))=(1muF)/(9muF)=(1)/(9)implies U_(S):U_(p)=1:9`