Question

In figure (b) What is the potential of point $A$ (in Volts) when $S$ is open?

Answer 1

As capacitor of $6\mu F$ and $2\mu F$ are in series the current on both the capacitor is same. Therefore,

$6V_6=2V_2$ and $V_6+V_2=100V$

$\Rightarrow V_2=75V$

$V_A=V_2-0=75V$

point A is at a potential of $75V$.