Question: What is the impedance of a circuit with a 4Ω resistor in series with a 3Ω inductor at a frequency of 60Hz (assuming inductive reactance of 18Ω)?
Options:
Correct Answer: 15Ω
Solution:
Z = R + jX = 4Ω + j18Ω; |Z| = √(4^2 + 18^2) = √(16 + 324) = √340 = 18.44Ω.