Deep Dive: E5C06
The correct answer is B: 50 ohms resistance in series with 25 ohms capacitive reactance. What does the impedance 50 - j25 ohms represent is 50 ohms resistance in series with 25 ohms capacitive reactance. Rectangular form R - jX means resistance in series with capacitive reactance. For amateur radio operators, this is important for circuit theory. Understanding this helps when interpreting impedance.
Why Other Answers Are Wrong
Option A: Incorrect. 50 ohms resistance in series with 25 ohms inductive reactance isn't correct - 50 - j25 is capacitive (negative j), not inductive. Inductive isn't correct. Option C: Incorrect. 25 ohms resistance in series with 50 ohms inductive reactance isn't correct - 50 - j25 is 50Ω resistance and 25Ω capacitive. 25Ω/50Ω swap isn't correct. Option D: Incorrect. 25 ohms resistance in series with 50 ohms capacitive reactance isn't correct - 50 - j25 is 50Ω resistance and 25Ω capacitive. 25Ω/50Ω swap isn't correct.
Exam Tip
Impedance 50 - j25 ohms = 50 ohms resistance in series with 25 ohms capacitive reactance. Think 'R' - 'j'X = 'R'esistance in series with 'C'apacitive reactance. Rectangular form R - jX means resistance in series with capacitive reactance. Not inductive, not swapped values - just 50Ω R, 25Ω capacitive.
Memory Aid
Impedance 50 - j25 ohms = 50 ohms resistance in series with 25 ohms capacitive reactance. Think 'R' - 'j'X = 'R'esistance + 'C'apacitive. Rectangular form R - jX means resistance in series with capacitive reactance. Important for circuit theory.
Real-World Example
The impedance 50 - j25 ohms: It represents 50 ohms resistance in series with 25 ohms capacitive reactance. The real part (50) is resistance, and the negative imaginary part (-j25) is capacitive reactance. This is what it represents - 50Ω R, 25Ω capacitive.
Source & Coverage
Question Pool: 2024-2028 Question Pool
Subelement: E5C
Reference: 2024-2028 Question Pool · E5 - Electrical Principles
Key Concepts
Verified Content
Question from the official FCC Extra Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the E5C topic.