Q18.The work function of a substance is 3. 0 eV. The longest wavelength of light that can cause the emission of photoelectrons from this substance is approximately: (1) 215 nm (2) 414 nm (3) 400 nm (4) 200 nm
What This Question Tests
This question is a direct application of the photoelectric effect concept, relating the work function to the longest wavelength (threshold wavelength) capable of causing emission.
Concepts Tested
Formulas Used
E = hν = hc/λ
W = hc/λ_threshold
📚 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?
11.9 — 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?
📋 Question Details
- Chapter
- Dual Nature of Matter
- Topic
- Photoelectric Effect
- Year
- 2024
- Shift
- 30 Jan Shift 1
- Q Number
- Q18
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 11: Dual Nature of Radiation and Matter
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