Question

Three identical capacitors, each of capacitance $C$, are connected in series with a battery of emf $V$ and get fully charged. Now, the battery is removed and the capacitors are connected in parallel with positive terminals are one point and negative terminals at other point. Then, the common potential will be :

• A. $V$
• B. $3V$
• C. $\frac{V}{3}$
• D. $0$

Answer 1

Answer: (C)

$\frac{V}{3}$

When capacitors are in series ,in this case capacitance of all are same and charge on all the capacitors are also same. Hence voltage will also be same
$V=3V^{\prime }$
$V^{\prime }=\frac{V}{3}$
Now if we connect them in parallel, all are at common potential difference V/3.