Technician exam question T4A09
Subelement T4, AMATEUR RADIO PRACTICES· Group T4A
How can you determine the length of time that equipment can be powered from a battery?
- A.Divide the watt-hour rating of the battery by the peak power consumption of the equipment
- B.Divide the battery ampere-hour rating by the average current draw of the equipment (correct answer)
- C.Multiply the watts per hour consumed by the equipment by the battery power rating
- D.Multiply the square of the current rating of the battery by the input resistance of the equipment
WhyYou can determine how long equipment can run on a battery by dividing the battery's ampere-hour rating by the equipment's average current draw. A battery's ampere-hour rating describes how much current it can supply over time, so dividing that rating by the equipment's average current draw gives an estimated run time in hours, answer B. A pairs a watt-hour rating with a peak, rather than average, power figure, mismatched units for this calculation, and C and D describe formulas that don't correspond to any real relationship between battery capacity and run time.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2026-2030 NCVEC Element 2 pool (public domain); the explanation above is original writing, see our methodology.
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