Q25.The difference between threshold wavelengths for two metal surfaces A and B having work function ϕA = 9 eV and ϕB = 4. 5 eV in nm is: {Given, hc = 1242 eV nm } (1) 540 (2) 276 (3) 264 (4) 138
What This Question Tests
This question is a direct application of the formula relating work function and threshold wavelength, requiring calculation of the difference in wavelengths.
Concepts Tested
Formulas Used
ϕ = 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?
11.6 — 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?
📋 Question Details
- Chapter
- Dual Nature of Matter
- Topic
- Photoelectric effect
- Year
- 2023
- Shift
- 13 Apr Shift 1
- Q Number
- Q25
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 11: Dual Nature of Radiation and Matter
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