What are the TheveninNorton equivalent resistance observed b

What are the Thevenin/Norton equivalent resistance observed by R_L for the circuit shown in the figure? Assume that R_1 = 230 Ohm and R_2 = 140 Ohm. Provide the answer to two decimal places. (Figure 1) Express your answer in complex from as follow (A + jB), Where A is the real nd B is the imaginary part.

Solution

R1 and R2 are parallel. Hence equivalent resistance of R1 and R2 = 140*230/(140+230) = 87.03 ohm = R12

R12 and -20j ohm are in parallel. hence equivalent impedence = 87.03*(-20j)/(87.03-20j) = R123

R123 and -80j ohm are in series. equivalent impedence = 87.03*(-20j)/(87.03-20j) -80j = (-1600 + 8703j)/(87.03-20j)

thevenin impedence = (-1600 + 8703j)/(87.03-20j)