Q20.When radiation of wavelength λ is incident on a metallic surface, the stopping potential of ejected photoelectrons is 4. 8 V . If the same surface is illuminated by radiation of double the previous wavelength, then the stopping potential becomes 1. 6 V . The threshold wavelength of the metal is: (1) 2λ (2) 4λ (3) 8λ (4) 6λ + N acts on a particle. The work done by this force when the particle is moved from
What This Question Tests
The question asks to compare the kinetic energies of an electron and a photon having the same de Broglie wavelength, requiring knowledge of their respective energy-momentum relations.
Concepts Tested
Formulas Used
λ = h/p
KE_electron = p^2/(2m)
KE_photon = hc/λ = pc
📚 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.
11.8 — 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?
11.6 — 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.
📋 Question Details
- Chapter
- Dual Nature of Matter
- Topic
- De Broglie wavelength
- Year
- 2021
- Shift
- 25 Jul Shift 2
- Q Number
- Q20
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 11: Dual Nature of Radiation and Matter
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