General exam question G5C12
Subelement G5, ELECTRICAL PRINCIPLES· Group G5C
G5C12
What is the capacitance of a 20-microfarad capacitor connected in series with a 50-microfarad capacitor?
- A.0.07 microfarads
- B.14.3 microfarads (correct answer)
- C.70 microfarads
- D.1,000 microfarads
WhyA 20-microfarad capacitor connected in series with a 50-microfarad capacitor has a combined capacitance of about 14.3 microfarads. Two capacitors in series combine as (C1 × C2) ÷ (C1 + C2), so 20 times 50 (1,000) divided by 70 comes out to about 14.3 microfarads, answer B. The other values don't follow from applying that two-capacitor series formula to 20 and 50 microfarads.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2023-2027 NCVEC Element 3 pool (public domain); the explanation above is original writing, see our methodology.
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