Circuit Theorems and Conversions - Engineering

Q1:

Find RN for the circuit given.

A 34 

B 68 

C 120 

D 154 

ANS:D - 154 

Just assume 2 things.
1, Short the voltage source.
2. Open the RL load.

And let as assume voltage source at the place of RLload. Now solve the problem 68ohms.

68ohms =34ohms, 34 in series with 120 ohms = 154 ohms total.