Figure shows the circuit that contains three resistances ( $9 \Omega$ each) and two inductors ( 4 mH

Question

Figure shows the circuit that contains three resistances ( $9 \Omega$ each) and two inductors ( 4 mH each). The reading of ammeter at the moment switch $K$ is turned ON , is $\_\_\_\_$ A.

Professor PC Thomas Classes · Answer

At the exact moment the switch is turned ON ($t=0$), an inductor opposes any sudden change in current, thereby acting as an open circuit (infinite resistance). Consequently, no current flows through the branches containing the inductors. The only current that flows from the battery must pass entirely through the single branch with just a resistor. Using Ohm's law, $I = \frac{V}{R} = \frac{9	ext{V}}{9\Omega} = 1	ext{ A}$.