Technician exam question T6B07
Subelement T6, ELECTRONIC AND ELECTRICAL COMPONENTS· Group T6B
T6B07
What causes a light-emitting diode (LED) to emit light?
- A.Forward current (correct answer)
- B.Reverse current
- C.Capacitively-coupled RF signal
- D.Inductively-coupled RF signal
WhyForward current causes a light-emitting diode (LED) to emit light. An LED emits light when current flows through it in the forward direction, causing electrons to recombine across the junction and release energy as photons, answer A. Reverse current (B) doesn't light an LED, it simply blocks conduction, and RF coupling, capacitive or inductive (C, D), isn't how an LED is normally driven.
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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