Question

The equivalent capacitance between the terminals $X$ and $Y$ in the figure shown will be -

• A. $100pF$
• B. $200pF$
• C. $300pF$
• D. $400pF$

Answer 1

The correct option is B $200pF$

Let two nodes $a$, $b$ between the terminal $X$ and $Y$.

Since between the node $Y$ and $b$ the two capacitors of $100pf$ are in parallel, between the node $a$ and $b$ the capacitor of $200pf$ is in series.

The equivalent capacitance between the node $Y$ and $b$ is given as,

$C_1=100||100$

$=200pf$

The equivalent capacitance between the node $Y$ and $a$ is given as,

$C_2=\left[\frac{\left(200\times 200\right)}{200+200}||100\right]$

$=200pf$

The equivalent capacitance between the node $Y$ and $X$ is given as,

$C=\left[\frac{\left(200\times 200\right)}{200+200}||100\right]$

$=200pf$

Thus, the equivalent capacitance between the terminals $X$ and $Y$ is $200pf$.