Question

Two capacitors are completely charged by a battery as shown in figure. Then battery is taken out and capacitor are connected together such that plates of opposite polarity are connected together. Select the correct statement :-

• A. No charge distribution will take place.
• B. Final potential on each capacitor is $\frac{V}{2}$
• C. Energy loss in charge distribution process is $\frac{4 C V^{2}}{3}$
• D. Final charge on each capacitor will be equal.

Answer 1

Answer: (C)

Now, polarity change

$V_{c o m m o n }=\frac{- C V + 2 C V}{3 C}=\frac{V}{3}$
Charge flow $\Rightarrow 2CV-\frac{2 C V}{3}\Rightarrow \frac{4 C V}{3}$
Energy loss
$=\frac{1}{2}CV^{2}+\frac{1}{2}2CV^{2}-\frac{1}{2}C\left(\frac{V}{3}\right)^{2}-\frac{1}{2}2C\left(\frac{V}{3}\right)^{2}$
$=\frac{4}{3}CV^{2}$