Q29.The stopping potential for photoelectrons emitted from a surface illuminated by light of wavelength 6630Å is 0. 42 V . If the threshold frequency is x × 1013 s, where x is (nearest integer): (Given, speed light = 3 × 108 m s−1 . Planck's constant = 6. 63 × 10−34 J s)
What This Question Tests
This question requires applying Einstein's photoelectric equation to find the threshold frequency using given stopping potential and incident wavelength.
Concepts Tested
Formulas Used
eV_s = hc/λ - hf_0
c = fλ
📚 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.
11.5 — In An Experiment On Photoelectric Effect, The Slope Of The Cut-Off Voltage
Physics Class 12 · Chapter 11
11.5 In an experiment on photoelectric effect, the slope of the cut-off voltage versus frequency of incident light is found to be 4.12 × 10–15 V s. Calculate the value of Planck’s constant.
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
- 2022
- Shift
- 26 Jun Shift 2
- Q Number
- Q29
- Type
- Numerical
- NCERT Ref
- Class 12 Physics Ch 11: Dual Nature of Radiation and Matter
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