Updated: Dec 9, 2025 | Source: 2024-2028 Question Pool | Topic: E5B
E5B12E5B

What is admittance?

Deep Dive: E5B12

The correct answer is A: The inverse of impedance. What is admittance is the inverse of impedance. Admittance Y = 1/Z. For amateur radio operators, this is important for circuit theory. Understanding this helps when working with admittance.

Why Other Answers Are Wrong

Option B: Incorrect. Term for gain of FET isn't admittance - admittance is inverse of impedance. FET gain isn't admittance. Option C: Incorrect. Inverse of reactance isn't admittance - admittance is inverse of impedance. Inverse of reactance isn't admittance. Option D: Incorrect. Term for on-impedance of FET isn't admittance - admittance is inverse of impedance. FET on-impedance isn't admittance.

Exam Tip

Admittance = inverse of impedance. Think 'A'dmittance = '1'/'I'mpedance. Admittance Y = 1/Z. Not FET gain, not inverse of reactance, not FET on-impedance - just inverse of impedance.

Memory Aid

Admittance = inverse of impedance. Think 'A'dmittance = '1'/'Z'. Admittance Y = 1/Z. Important for circuit theory.

Real-World Example

Admittance: It's the inverse of impedance. If impedance Z = 50 ohms, then admittance Y = 1/50 = 0.02 siemens. This is what admittance is - the inverse of impedance.

Source & Coverage

Question Pool: 2024-2028 Question Pool

Subelement: E5B

Reference: 2024-2028 Question Pool · E5 - Electrical Principles

Key Concepts

Admittance Inverse of impedance Circuit theory

Verified Content

Question from the official FCC Extra Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the E5B topic.