Technician exam question T5B11
Subelement T5, ELECTRICAL PRINCIPLES· Group T5B
T5B11
Which decibel value represents a power increase from 20 watts to 200 watts?
- A.10 dB (correct answer)
- B.12 dB
- C.18 dB
- D.28 dB
WhyA power increase from 20 watts to 200 watts represents 10 dB. Going from 20 watts to 200 watts is a tenfold increase in power, and a tenfold power increase corresponds to exactly 10 dB, ten times the base-10 logarithm of 10, answer A. B, C, and D don't match the decibel value for a clean tenfold power ratio.
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.