Q29.The energy band gap of semiconducting material to produce violet (wavelength = 4000 Å) LED is _____ eV. (Round off to the nearest integer).
What This Question Tests
This question directly applies the relationship between photon energy and wavelength (E = hc/λ) to determine the energy band gap required for an LED emitting light of a specific wavelength.
Concepts Tested
Formulas Used
E = hc/λ
📚 NCERT Sections This Tests
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?
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?
12.5 — A Hydrogen Atom Initially In The Ground Level Absorbs A Photon,
Physics Class 12 · Chapter 12
12.5 A hydrogen atom initially in the ground level absorbs a photon, which excites it to the n = 4 level. Determine the wavelength and frequency of photon.
📋 Question Details
- Chapter
- Semiconductor
- Topic
- LED and Energy Band Gap
- Year
- 2022
- Shift
- 25 Jul Shift 1
- Q Number
- Q29
- Type
- Numerical
- NCERT Ref
- Class 12 Physics Ch 14: Semiconductor Electronics
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