With 10 V dc connected at port A in the linear nonreciprocal two-port network shown below, the following were observed: (i) 1^$\Omega$connected at port B draws a current of 3 A (ii) 2.5 ^$\Omega$ connected at port B draws a current of 2 A With 10 V dc connected at port A, the current drawn by 7 ^$\Omega$connected at port B is

 Using Y-admittance model to figure out current for port B: I₄ = Y₂₁.V1 + Y₂₂.V2 (i) from the 1st condition, -3 = Y₂₁.10 + Y₂₂.3 (since V2 = - I₄ *RL = -(-3)*1 = 3V) (ii) from the 2nd condition, -2 = Y₂₁.10 + Y₂₂.5 (since V2 = - I₄ *RL = -(-2)*2.5 = 5V) Solving these 2 equations, we get : Y₂₁ = -9/20 and Y₂₂ = 1/2 Hence, I₄ = (-9/20).V1 + (1/2).V2 Given, V1 = 10V and V2 = (-I₄ * 7) Substituting, We get I₄ = -1A Ans : Current drawn by the 7$\Omega$ load resistor = -I₄ = 1A