Question

An electrical circuit is shown in the given figure. The resistance of each voltmeter is infinite and each ammeter is $100\Omega$. The charge on the capacitor of $100\mu F$ in steady state is 4 mC. Choose correct statements (s) regarding the given circuit

• A. Reading of voltmeter $V_2$ is 16V
• B. Reading of ammeter $A_1$ is zero and $A_2$ is 1/25 A
• C. Reading of voltmeter $V_1$ is 40 V
• D. EMF of the ideal cell is 66 V

Answer 1

Answer: (B), (C)

The correct options are
B Reading of ammeter $A_1$ is zero and $A_2$ is 1/25 A
C Reading of voltmeter $V_1$ is 40 V

In steady state current through capacitor wire is zero. So ammeter reading $A_1$ is zero and current flow through $200\Omega ,900\Omega ,A_2$.
Potential across the capacitor is $V_c=V_1=\frac{q}{C}=\frac{4\times {10}^{-3}}{100\times {10}^{-6}}=40V$
Now this is potential across the total resistance $=900+$ resistance of $A_2=900+100=1000\Omega$
Thus the reading of $A_2$ is $I=\frac{V_1}{1000}=40/1000=\left(1/25\right)A$
As $1000\Omega$ and $200\Omega$ are in series so current through is equal to $I$.
Thus, $V_2=V_{200}=200I=200/25=8V$
Emf of cell is $E=V_1+V_2=40+8=48V$