the color of light by light emitting diode depends upon
Correct answer: D. type of semiconductor
- A. forward voltage
- B. reverse current
- C. forward current
- D. type of semiconductor
Explanation
The color of light emitted by a light-emitting diode (LED) depends on the d. Type of semiconductor used in its construction.Here's why:LEDs and semiconductors: LEDs are semiconductor devices that convert electrical energy into light energy. Different types of semiconductors have different band gaps, which are the energy differences between the valence band and conduction band.Band gap and light emission: When an electron in the conduction band recombines with a hole in the valence band, it releases energy in the form of a photon. The energy of the emitted photon (which determines its color) is directly related to the band gap of the semiconductor material used in the LED.Therefore, the type of semiconductor used in the LED determines the band gap and consequently, the color of the emitted light
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About Electromagnetic Waves
Electromagnetic waves consist of mutually perpendicular, oscillating electric and magnetic fields that also remain perpendicular to the direction of propagation. They travel through vacuum at the speed of light and include radio waves, microwaves, infrared, visible, ultraviolet, X-rays and gamma rays. Unlike mechanical waves, they do not require a material medium.
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