Question T6A05
From subelement T6 - T6A
What type of electrical component consists of conductive surfaces separated by an insulator?
Why is this correct?
A capacitor consists of conductive surfaces (metal plates) separated by an insulator called a dielectric. This physical structure allows capacitors to store energy in an electric field between the plates. Resistors use resistive materials to oppose current flow, potentiometers are variable resistors with sliding contacts, and oscillators are circuits that generate signals—none have the plate-and-insulator construction that defines a capacitor.
Memory tip
Remember the pattern: component construction often reveals its function. When you see 'conductive surfaces separated by insulator,' think energy storage in an electric field. This physical description appears in multiple capacitor questions, making it a reliable identifier across different test scenarios.
Learn more
In practical amateur radio circuits, you'll encounter capacitors everywhere—from power supply filtering to antenna tuning networks. The plate-and-dielectric structure enables their versatility: blocking DC while passing AC, storing charge for power smoothing, and creating frequency-selective circuits when paired with inductors. Understanding this fundamental construction helps you troubleshoot circuits and select appropriate component types for specific applications.
Think about it
Why do you think the physical separation between conductive plates is essential for a capacitor's ability to store electrical energy?