Question

What is equivalent capacitance of circuit between points $A$ and $B$?

• A. $\frac{2}{3}\mu F$
• B. $\frac{4}{3}\mu F$
• C. Infinite
• D. $\left(1+\sqrt{3}\right)\mu F$

Answer 1

Answer: (B)

The effective circuit is shown in figure.
The capacitance of upper series,
$\frac{1}{C}=\frac{1}{1}+\frac{1}{3}+\frac{1}{9}+\frac{1}{27}+----\infty$
$\therefore C=\frac{2}{3}\mu C$
Now $C_{AB}=2C=\frac{4}{3}\mu F$