Q19.A light emitting diode (LED) is fabricated using GaAs semiconducting material whose band gap is 1.42eV. The wavelength of light emitted from the LED is : (1) 1400 nm (2) 650 nm (3) 875 nm (4) 1243 nm
What This Question Tests
This question relates the band gap energy of a semiconductor material to the wavelength of light emitted by an LED, using the photon energy formula.
Concepts Tested
Formulas Used
E = hc/λ
📚 NCERT Sections This Tests
11.9 — Light Of Wavelength 488 Nm Is Produced By An Argon Laser Which Is
Physics Class 12 · Chapter 11
11.9 Light of wavelength 488 nm is produced by an argon laser which is used in the photoelectric effect. When light from this spectral line is incident on the emitter, the stopping (cut-off) potential of photoelectrons is 0.38 V. Find the work function of the material from which the emitter is made.
11.7 — The Work Function For A Certain Metal Is 4.2 Ev. Will This Metal Give
Physics Class 12 · Chapter 11
11.7 The work function for a certain metal is 4.2 eV. Will this metal give hotoelectric emission for incident radiation of wavelength 330 nm?
12.3 — A Difference Of 2.3 Ev Separates Two Energy Levels In An Atom. What
Physics Class 12 · Chapter 12
12.3 A difference of 2.3 eV separates two energy levels in an atom. What is the frequency of radiation emitted when the atom make a transition from the upper level to the lower level?
📋 Question Details
- Chapter
- Semiconductor
- Topic
- LED (Light Emitting Diode)
- Year
- 2024
- Shift
- 09 Apr Shift 1
- Q Number
- Q19
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 14: Semiconductor Electronics: Materials, Devices and Simple Circuits
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