Given is the circuit below The node connected to ground is t

Given is the circuit below. The node connected to ground is the reference node, the voltages at nodes a (Va), b (Vb), c (Ve), and d (Vd) are unknown and have to be determined. The general version of the node voltage analysis tells us to apply KCL at each node with an unknown voltage. The following equation displays the correct KCL for node d: 6 Is reference Re R3 + R +-=0 R6 R3+R4 R9

Solution

1) at node d=> current flowing towards d are from c to d and b to d while current away from d is from d to reference node so applying kcl rule currents flowing towards node =currents flowing away from node d

   so (Vd-Vc)/R6 + (Vd-Vb)/(R3+R4) = Vd/R9

option d satisfies the above equation

2) here no of nodes =3

Va,Vb and Vc and Vc is connected to source voltage Vs=> Vc=Vs

unknown voltages will be Va and Vb