What causes a light-emitting diode (LED) to emit light?

What causes a light-emitting diode (LED) to emit light?

• A. Reverse voltage
• B. Forward current
• C. Direct frequency
• D. Inductive charge

Answer: (B)

A light-emitting diode (LED) emits light due to the flow of forward current. When a forward voltage is applied across the LED, electrons in the semiconductor material are energized. As these electrons move from a higher energy level to a lower energy level, they release energy in the form of photons, which we perceive as visible light. The specific color of light emitted depends on the material properties of the LED and the energy gap between the conduction and valence bands. In contrast, reverse voltage applies a negative potential that can preventcurrent flow through the diode and does not lead to light emission. The term "direct frequency" is unrelated to how diodes operate and does not describe a mechanism for light emission. Inductive charge pertains to inductors and their behavior in electrical circuits, not to how diodes function. Hence, the correct choice accurately describes the phenomenon where a forward current causes the LED to emit light.

A light-emitting diode (LED) emits light due to the flow of forward current. When a forward voltage is applied across the LED, electrons in the semiconductor material are energized. As these electrons move from a higher energy level to a lower energy level, they release energy in the form of photons, which we perceive as visible light. The specific color of light emitted depends on the material properties of the LED and the energy gap between the conduction and valence bands.

In contrast, reverse voltage applies a negative potential that can preventcurrent flow through the diode and does not lead to light emission. The term "direct frequency" is unrelated to how diodes operate and does not describe a mechanism for light emission. Inductive charge pertains to inductors and their behavior in electrical circuits, not to how diodes function. Hence, the correct choice accurately describes the phenomenon where a forward current causes the LED to emit light.