NEET2017PhysicsAlternating CurrentActual
Figure shows a circuit contains three identical resistors with resistance R = 9.0   Ω each, two identical inductors with inductance L = 2.0    mH each, and an ideal battery with emf ε =   18   V . The current i through the battery just after the switch closed is:
Options
- A2    mA
- B0.2   A
- C2   A
- D0   A
Correct answer
C. 2   A
Step-by-step solution
When the switch is just closed, the inductors show infinite opposition and hence both the branches with Inductor-Resistor combination do not really participate in the circuit. At t = 0 , no current flows through R 1 and R 3 At t = 0 inductor behaves like an open wire. i = ε R 2 = 18 9 = 2  A