General exam question G5B12
Subelement G5, ELECTRICAL PRINCIPLES· Group G5B
G5B12
What is the RMS voltage across a 50-ohm dummy load dissipating 1200 watts?
- A.173 volts
- B.245 volts (correct answer)
- C.346 volts
- D.692 volts
WhyA 50-ohm dummy load dissipating 1200 watts has an RMS voltage across it of about 245 volts. RMS voltage across a resistive load can be found by rearranging P = V²/R to V = √(P × R), so the square root of 1,200 watts times 50 ohms (60,000) comes out to about 245 volts, answer B. The other values don't follow from applying that relationship to 1,200 watts across 50 ohms.
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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