What current flows equally on all conductors of an unshielded multiconductor cable?
The correct answer is B: Common-mode current. What current flows equally on all conductors of an unshielded multiconductor cable is common-mode current. Common-mode current flows equally on all conductors. For amateur radio operators, this is important for understanding cable currents. Understanding this helps when troubleshooting interference.
Exam Tip
Current flowing equally on all conductors = common-mode current. Think 'C'ommon-'M'ode = 'C'urrent on 'M'any conductors equally. Common-mode current flows equally on all conductors. Not differential-mode, not reactive only, not magnetically-coupled only - just common-mode.
Memory Aid
"Current flowing equally on all conductors = common-mode current. Think 'C'ommon-'M'ode = 'E'qual on 'A'll. Common-mode current flows equally on all conductors. Important for understanding cable currents."
Real-World Application
An unshielded multiconductor cable: Common-mode current flows equally on all conductors. This is current that flows in the same direction on all conductors, as opposed to differential-mode current which flows in opposite directions. This is the current - common-mode current.
Key Concepts
Why Other Options Are Wrong
Option A (Differential-mode current): Incorrect. Differential-mode current doesn't flow equally - it flows in opposite directions on different conductors. Differential-mode isn't equal.
Option C (Reactive current only): Incorrect. Reactive current only isn't the answer - common-mode current flows equally. Reactive current isn't the answer.
Option D (Magnetically-coupled current only): Incorrect. Magnetically-coupled current only isn't the answer - common-mode current flows equally. Magnetically-coupled isn't the answer.
题目解析
The correct answer is B: Common-mode current. What current flows equally on all conductors of an unshielded multiconductor cable is common-mode current. Common-mode current flows equally on all conductors. For amateur radio operators, this is important for understanding cable currents. Understanding this helps when troubleshooting interference.
考试技巧
Current flowing equally on all conductors = common-mode current. Think 'C'ommon-'M'ode = 'C'urrent on 'M'any conductors equally. Common-mode current flows equally on all conductors. Not differential-mode, not reactive only, not magnetically-coupled only - just common-mode.
记忆口诀
Current flowing equally on all conductors = common-mode current. Think 'C'ommon-'M'ode = 'E'qual on 'A'll. Common-mode current flows equally on all conductors. Important for understanding cable currents.
实际应用示例
An unshielded multiconductor cable: Common-mode current flows equally on all conductors. This is current that flows in the same direction on all conductors, as opposed to differential-mode current which flows in opposite directions. This is the current - common-mode current.
错误选项分析
Option A (Differential-mode current): Incorrect. Differential-mode current doesn't flow equally - it flows in opposite directions on different conductors. Differential-mode isn't equal. Option C (Reactive current only): Incorrect. Reactive current only isn't the answer - common-mode current flows equally. Reactive current isn't the answer. Option D (Magnetically-coupled current only): Incorrect. Magnetically-coupled current only isn't the answer - common-mode current flows equally. Magnetically-coupled isn't the answer.
知识点
Unshielded multiconductor cable, Current flows equally, Common-mode current, Cable currents
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.