We have a linear resistive circuit containing both independent and dependent sources. Two terminals labled a and b come from the circuit.
Find the Thevenin equivalent if the following experimental data is collected by attaching different load resistances to the two terminals.
RL = 20 K; Vab = 100 V
RL = 50 K; Vab = 200 V
Voltage division will give us a relationship among the various parameters:
Vab = VTh [RL / (RL + RTh)]
Plugging in the two pairs of known values obtained by experiment gives two equations in two unknowns
100 = VTh [20K / (20K + RTh)]
2M + 100 RTh = 20K VTh
20K VTh - 100 RTh = 2M (equation 1)200 = VTh [50K / (50K + RTh)]
10M + 200 RTh = 50K VTh
50K VTh - 200 RTh = 10M (equation 2)
Solving these two equations gives
VTh = 600 V
RTh = 100 KW
Thus the Thevenin equivalent circuit is
