Three coils of inductance, L₁ = 2 H, L₂ = 3 H and L₃ = 6 H are connected so that they are separated from each other. To obtain the effective inductance of 18 11 H between points A and B, out of the following figures, the correct one is

Step-by-step solution

Given inductances are L₁ = 2 H, L₂ = 3 H, and L₃ = 6 H. Let us calculate the equivalent inductance for each given circuit: For circuit (P), the inductors are in series: L_ eq = L₁ + L₂ + L₃ = 2 + 3 + 6 = 11 H. For circuit (Q), the inductors are in parallel: 1 L_ eq = 1 L₁ + 1 L₂ + 1 L₃ = 1 2 + 1 3 + 1 6 = 3 + 2 + 1 6 = 1 L_ eq = 1 H. For circuit (R), L₁ and L₂ are in series, and their combination is in parallel with L₃ : L_ eq = (L₁ + L₂)L₃ (L₁ + L₂) + L₃ = (2 + 3) 6 (2 + 3) + 6 = 30 11 H. For circuit (S), L₂ and L