G6A11: Inductor: What happens when an inductor is operated

Q: What happens when an inductor is operated above its self-resonant frequency?

The correct answer is C: It becomes capacitive. The correct answer is C: It becomes capacitive. What happens when an inductor is operated above its self-resonant frequency is that it becomes capacitive. Above self-resonance, the inductor's parasitic capacitance dominates, making it behave like a capacitor. For amateur radio operators, this is important for RF circuit design. Understanding this helps when using inductors at high frequencies.

Updated: Dec 9, 2025 | Source: 2023-2027 Question Pool | Topic: G6A

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What happens when an inductor is operated above its self-resonant frequency?

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Deep Dive: G6A11

The correct answer is C: It becomes capacitive. What happens when an inductor is operated above its self-resonant frequency is that it becomes capacitive. Above self-resonance, the inductor's parasitic capacitance dominates, making it behave like a capacitor. For amateur radio operators, this is important for RF circuit design. Understanding this helps when using inductors at high frequencies.

Why Other Answers Are Wrong

Option A: Incorrect. Reactance doesn't continue increasing above self-resonance - above resonance, the inductor becomes capacitive, so reactance decreases. Behavior changes at resonance. Option B: Incorrect. Harmonics aren't generated by operating above self-resonance - harmonics come from non-linear operation, not from frequency above resonance. Harmonics aren't the issue. Option D: Incorrect. Catastrophic failure isn't likely - the inductor just behaves differently (capacitively), it doesn't fail. Failure isn't the result.

Exam Tip

Inductor above self-resonance = becomes capacitive. Think 'A'bove 'R'esonance = 'A'cting 'R'everse (capacitive). Above self-resonant frequency, parasitic capacitance dominates, making inductor behave like capacitor. Not increasing reactance, not harmonics, not failure - just becomes capacitive.

Memory Aid

Inductor above self-resonance = becomes capacitive. Think 'A'bove 'R'esonance = 'A'cting 'R'everse. Above self-resonant frequency, parasitic capacitance dominates, making inductor behave like capacitor. Important for RF design.

Real-World Example

An inductor has a self-resonant frequency of 10 MHz. Below 10 MHz, it behaves as an inductor. Above 10 MHz, the parasitic capacitance dominates, and it behaves like a capacitor. This is why inductors have frequency limits - above self-resonance, they don't work as inductors anymore.

Source & Coverage

Question Pool: 2023-2027 Question Pool

Subelement: G6A

Reference: 2023-2027 Question Pool · G6 - Circuit Components

Key Concepts

Inductor Self-resonant frequency Capacitive behavior Parasitic capacitance

Verified Content

Question from the official FCC General Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the G6A topic.