FCC Question Pool Review

Technician Class (Element 2) • 2022-2026

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Question T5D13

From subelement T5 - T5D

T5D13
Answer: A

In which type of circuit is DC current the same through all components?

ASeries
BParallel
CResonant
DBranch

Why is this correct?

In a series circuit, current is the same through all components because there's only one path for electrons to flow. Like water through a single pipe, all current must pass through each component sequentially. In parallel circuits, current divides among multiple paths, so each branch carries different amounts. Resonant circuits describe frequency behavior, not current distribution. Branch circuits are parallel subcircuits.

Memory tip

Remember: Series = Same current, Parallel = same Voltage. In series, think of components as links in a chain—break one link and the whole chain fails because current has nowhere else to go. This fundamental difference affects troubleshooting and component selection in amateur radio circuits.

Learn more

Series circuits demonstrate Kirchhoff's Current Law practically: current entering any point equals current leaving. This principle becomes crucial when designing antenna tuning circuits, where precise current control through components like loading coils determines radiation efficiency. Understanding series current behavior helps amateur operators calculate proper component ratings and predict circuit behavior under varying load conditions.

Think about it

Why do you think Christmas lights wired in series all go out when one bulb fails, while household outlets on the same circuit stay powered when one device is unplugged?