Answer: 6 V.
- A 3 V
- B 4.5 V
- C 9 V
- D 6 V
Correct answer: D. 6 V
Explanation: Series capacitance = (3×6)/(3+6) = 2 µF, so Q = 2 µF × 9 V = 18 µC. Across the 3 µF: V = Q/C = 18/3 = 6 V.
Field lines (radial) and equipotential lines (concentric circles) of a point charge. Equipotential surfaces are always perpendicular to the field lines. Image: Sjlegg, Public Domain, via Wikimedia Commons.
Concept context
Electric potential, equipotential surfaces, potential energy of charge systems, conductors, dielectrics, capacitors, combinations, and energy storage.
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