Q28.For LED's to emit light in visible region of electromagnetic light, it should have energy band gap in the range of: (1) 0.1eV to 0.4eV (2) 0.5eV to 0.8eV (3) 0.9eV to 1.6eV (4) 1.7eV to 3.0eV
What This Question Tests
This conceptual question checks the basic knowledge about LEDs, specifically the required energy band gap for emitting light in the visible region of the electromagnetic spectrum.
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?
11.3 — The Photoelectric Cut-Off Voltage In A Certain Experiment Is 1.5 V.
Physics Class 12 · Chapter 11
11.3 The photoelectric cut-off voltage in a certain experiment is 1.5 V. What is the maximum kinetic energy of photoelectrons emitted?
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?
📋 Question Details
- Chapter
- Semiconductor
- Topic
- Light Emitting Diode (LED)
- Year
- 2014
- Shift
- 12 Apr Online
- Q Number
- Q28
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 14: Semiconductor Electronics: Materials, Devices and Simple Circuits
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