Q17.When the wavelength of radiation falling on a metal is changed from 500 nm to 200 nm, the maximum kinetic energy of the photoelectrons becomes three times larger. The work function of the metal is close to: JEE Main 2020 (03 Sep Shift 1) JEE Main Previous Year Paper (1) 0. 81 eV (2) 1. 02 eV (3) 0. 52 eV (4) 0. 61 eV
What This Question Tests
This problem requires setting up two photoelectric equations for two different incident wavelengths and solving them simultaneously to find the work function of the metal.
Concepts Tested
Formulas Used
KE_max = hc/λ - φ
📚 NCERT Sections This Tests
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?
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?
11.2 — The Work Function Of Caesium Metal Is 2.14 Ev. When Light Of
Physics Class 12 · Chapter 11
11.2 The work function of caesium metal is 2.14 eV. When light of frequency 6 ×1014Hz is incident on the metal surface, photoemission of electrons occurs. What is the (a) maximum kinetic energy of the emitted electrons, (b) Stopping potential, and (c) maximum speed of the emitted photoelectrons?
📋 Question Details
- Chapter
- Dual Nature of Matter
- Topic
- Photoelectric Effect
- Year
- 2020
- Shift
- 03 Sep Shift 1
- Q Number
- Q17
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 11: Dual Nature of Radiation and Matter
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