In capacitor construction, which arrangement correctly describes a basic capacitor used in electronics: what materials are separated by what?

Introduction / Context:
A capacitor stores energy in the electric field between two separated conductors. Its simplest physical form is two plates with an insulating material between them. Recognizing the correct construction helps in understanding capacitance formulas, breakdown voltage, leakage, and how material choices affect performance in power supplies, RF circuits, and signal coupling/decoupling applications.

Given Data / Assumptions:

• Idealized basic capacitor model.
• Focus on structural arrangement, not specific dielectric types.
• Standard electronic components (not exotic structures).

Concept / Approach:
Capacitance C depends on plate area A, plate separation d, and dielectric constant k: C = k * epsilon_0 * A / d. This relationship assumes two conductive plates (electrodes) separated by a dielectric (insulator). Coils are associated with inductors, not capacitors, and “two dielectrics separated by a conductor” inverts the proper arrangement. Correct identification of the structure is fundamental to predicting how geometry and materials change capacitance and voltage rating.

Step-by-Step Solution:
Recall the definition of capacitance: charge stored per volt (C = Q/V).Map the physical meaning: electric field confined in a dielectric between conductors.Identify the arrangement that yields this field: two conductors with a dielectric between them.Select option A.

Verification / Alternative check:
Look at common parts: ceramic multilayer capacitors, aluminum electrolytics, film capacitors—all consist of conductive foils or electrodes separated by a dielectric layer. This confirms the general structural statement.

Why Other Options Are Wrong:
B reverses conductor/insulator roles. C and D describe coils, which define inductors, not capacitors. “None” fails because A captures the textbook construction.

Common Pitfalls:
Confusing dielectric breakdown limits with conductor spacing only; ignoring that real capacitors include parasitic inductance and resistance, but those do not alter the core plate-dielectric-plate construction.

Final Answer:
two conductors separated by a dielectric