Q. In the circuit shown, the internal resistance of the cell is negligible. The steady state current in the 2$\ \Omega$ resistance is

A) 0.6A
B) 1.2A
C) 0.9A
D) 1.5A
Explanation

(c) In the steady state, no current flows through the branch containing the capacitor. So, the equivalent circuit will be of the form as shown below:
The effective resistance of the circuit is
$R = \frac{2 \times 3}{2 + 3} + 2.8 = 1.2 + 2.8 = 4\Omega$
The current through the circuit is
$i = \frac{E}{R} = \frac{6}{4} = 1.5A$
Let current $i_{1}$ flows through 2$\Omega$ resistance.
$\therefore\ \ \ 2 \times i_{1} = \left( i - i_{1} \right) \times 3$
$\Longrightarrow \ \ 2i_{1} = \left( 1.5 - i_{1} \right) \times 3$
$\Longrightarrow 2i_{1} = 4.5 - 3i_{1}$
$\Longrightarrow 5i_{1} = 4.5$
$\Longrightarrow i_{1} = 0.9A$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.