Which of the following is opposition to the flow of alternating current in an inductor?
The correct answer is D: Reactance. The opposition to the flow of alternating current in an inductor is reactance. Inductive reactance (XL) is the opposition that inductors present to AC current. For amateur radio operators, this is a fundamental circuit concept. Understanding this helps when working with inductors.
Exam Tip
Inductor AC opposition = reactance. Think 'I'nductor = 'I'nductive 'R'eactance. Inductors present reactance (specifically inductive reactance XL) to AC current. Not conductance, reluctance, or admittance - just reactance.
Memory Aid
"Inductor AC opposition = reactance. Think 'I'nductor = 'I'nductive 'R'eactance. Inductors present reactance (XL) to AC current. Frequency-dependent opposition to AC."
Real-World Application
An inductor in an AC circuit presents inductive reactance (XL = 2πfL), which opposes AC current flow. The reactance increases with frequency - higher frequency means more opposition. This is the opposition that inductors present to AC.
Key Concepts
Why Other Options Are Wrong
Option A (Conductance): Incorrect. Conductance is the inverse of resistance (1/R), not the opposition in an inductor. Conductance isn't for inductors.
Option B (Reluctance): Incorrect. Reluctance is a magnetic circuit term, not an electrical circuit term for AC opposition. Reluctance is for magnetic circuits.
Option C (Admittance): Incorrect. Admittance is the inverse of impedance (1/Z), not the opposition in an inductor. Admittance isn't the opposition.
题目解析
The correct answer is D: Reactance. The opposition to the flow of alternating current in an inductor is reactance. Inductive reactance (XL) is the opposition that inductors present to AC current. For amateur radio operators, this is a fundamental circuit concept. Understanding this helps when working with inductors.
考试技巧
Inductor AC opposition = reactance. Think 'I'nductor = 'I'nductive 'R'eactance. Inductors present reactance (specifically inductive reactance XL) to AC current. Not conductance, reluctance, or admittance - just reactance.
记忆口诀
Inductor AC opposition = reactance. Think 'I'nductor = 'I'nductive 'R'eactance. Inductors present reactance (XL) to AC current. Frequency-dependent opposition to AC.
实际应用示例
An inductor in an AC circuit presents inductive reactance (XL = 2πfL), which opposes AC current flow. The reactance increases with frequency - higher frequency means more opposition. This is the opposition that inductors present to AC.
错误选项分析
Option A (Conductance): Incorrect. Conductance is the inverse of resistance (1/R), not the opposition in an inductor. Conductance isn't for inductors. Option B (Reluctance): Incorrect. Reluctance is a magnetic circuit term, not an electrical circuit term for AC opposition. Reluctance is for magnetic circuits. Option C (Admittance): Incorrect. Admittance is the inverse of impedance (1/Z), not the opposition in an inductor. Admittance isn't the opposition.
知识点
Inductor, Reactance, Inductive reactance, AC opposition
Verified Content
Question from official FCC General Class question pool. Explanation reviewed by licensed amateur radio operators.