Using Superposition theorem for independent sources (i.e. using ohm's law and applying the current divider rule) I would like to check the equations used to find the voltage across R4. RL is known so workings do not need to be shown.
(See attached file for circuit diagram)
This is a check for me as I am studying for an exam, so please show all working so as if I have gone wrong I can see why.
a) Open The current source Is.
Total Series Impedance Z = (R1||RL) + (R3||R4) + R2, where || means Parallel
Hence V = Vs * [ (R3||R4)/ Z ] = Vc ...
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