Question

Figure shows a part of network of a capacitor and resistors. The potential indicated at A, B and C are with respect to the ground. Find the charge on the capacitor (in $\mu$C) in steady state.

Answer 1

In the steady state the capacitor is fully charged so no current will pass through resistor $8\Omega$.

Let the potential at the junction be e V.

As sum of the currents at junction =0

$\frac{4-e}{4}+\frac{6-e}{2}+\frac{8-e}{4}=0e=6V$

So voltage across capacitor is 4 V.

Thus charge on the capacitor is $Q=CV=1\times {10}^{-6}\times 4=4\mu C$