Q25.When a certain photosensitive surface is illuminated with a monochromatic light of frequency ν, the stopping potential of the photo current is −V02 . When the surface is illuminated by monochromatic light of frequency ν 2 , the stopping potential is −V0. The threshold frequency for photoelectric emission is (1) 5v (2) 3v 3 2 (3) 4 v (4) 2v 3
What This Question Tests
The question requires setting up and solving two simultaneous equations based on Einstein's photoelectric equation for different frequencies and stopping potentials to find the threshold frequency.
Concepts Tested
Formulas Used
eV_s = hν - hν₀
📚 NCERT Sections This Tests
11.6 — The Threshold Frequency For A Certain Metal Is 3.3 × 1014 Hz. If Light
Physics Class 12 · Chapter 11
11.6 The threshold frequency for a certain metal is 3.3 × 1014 Hz. If light of frequency 8.2 × 1014 Hz is incident on the metal, predict the cut- off voltage for the photoelectric emission.
11.8 — Light Of Frequency 7.21 × 1014 Hz Is Incident On A Metal Surface.
Physics Class 12 · Chapter 11
11.8 Light of frequency 7.21 × 1014 Hz is incident on a metal surface. Electrons with a maximum speed of 6.0 × 105 m/s are ejected from the surface. What is the threshold frequency for photoemission of electrons?
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?
📋 Question Details
- Chapter
- Dual Nature of Matter
- Topic
- Photoelectric effect
- Year
- 2019
- Shift
- 12 Jan Shift 2
- Q Number
- Q25
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 11: Dual Nature of Radiation and Matter
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