Two identical capacitors are connected in parallel across a poten…

MCQ

Two identical capacitors are connected in parallel across a potenial difference $V$. After they are fully charged, the positive plate of first capacitor is connected to negative plate of second and negative plate of first is connected to positive plate of other. The loss of energy will be

A
$\frac{1}{2} C V^2$
✓
$CV ^2$
C
$\frac{1}{4} C V^2$
D
$0$

✓

Answer

Correct option: B.

$CV ^2$

b
(b)

$U_i=\frac{1}{2} C V^2+\frac{1}{2} C V^2=C V^2$

$U_f=0$

$\Delta U=C V^2$

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