Updated: Dec 9, 2025 | Source: 2023-2027 Question Pool | Topic: G5A
G5A07G5A

What is the term for the inverse of impedance?

Deep Dive: G5A07

The correct answer is D: Admittance. The term for the inverse of impedance is admittance. Admittance (Y) = 1/Z, where Z is impedance. For amateur radio operators, this is a fundamental circuit concept. Understanding this helps when working with impedance and admittance.

Why Other Answers Are Wrong

Option A (Conductance): Incorrect. Conductance is the inverse of resistance (1/R), not impedance. Conductance is for DC resistance, not AC impedance. Option B (Susceptance): Incorrect. Susceptance is the imaginary part of admittance, not the inverse of impedance. Susceptance is a component of admittance. Option C (Reluctance): Incorrect. Reluctance is a magnetic circuit term, not an electrical circuit term. Reluctance is for magnetic circuits, not electrical.

Exam Tip

Inverse of impedance = admittance. Think 'A'dmittance = 'A'dmittance is '1'/Z. Admittance (Y) = 1/Z, where Z is impedance. Not conductance (1/R), not susceptance (part of Y), not reluctance (magnetic) - just admittance.

Memory Aid

Inverse of impedance = admittance. Think 'A'dmittance = 'A'dmittance is '1'/Z. Admittance (Y) = 1/Z, where Z is impedance. Represents ease of current flow, opposite of impedance.

Real-World Example

An impedance of 50 ohms has an admittance of 1/50 = 0.02 siemens. Admittance is the inverse of impedance - it represents how easily current flows, while impedance represents opposition. Admittance is useful in parallel circuit calculations.

Source & Coverage

Question Pool: 2023-2027 Question Pool

Subelement: G5A

Reference: 2023-2027 Question Pool · G5 - Electrical Principles

Key Concepts

Admittance Inverse of impedance Impedance Circuit theory

Verified Content

Question from the official FCC General Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the G5A topic.