General exam question G5B04
Subelement G5, ELECTRICAL PRINCIPLES· Group G5B
G5B04
How many watts of electrical power are consumed by a 12 VDC light bulb that draws 0.2 amperes?
- A.2.4 watts (correct answer)
- B.24 watts
- C.6 watts
- D.60 watts
WhyA 12 VDC light bulb drawing 0.2 amperes consumes 2.4 watts. Power is the product of voltage and current, P = VI, so 12 volts times 0.2 amperes comes out to 2.4 watts, answer A. The other values are off by roughly a factor of 10 or more from that straightforward multiplication.
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.
Related questions
- G5B01What dB change represents a factor of two increase or decrease in power?
- G5B02How does the total current relate to the individual currents in a circuit of parallel resistors?
- G5B03How many watts of electrical power are consumed if 400 VDC is supplied to an 800-ohm load?
- G5B05How many watts are consumed when a current of 7.0 milliamperes flows through a 1,250-ohm resistance?
- G5B06What is the PEP produced by 200 volts peak-to-peak across a 50-ohm dummy load?