Q26.In a photoelectric effect experiment, the threshold wavelength of light is 380 nm . If the wavelength of incident light is 260 nm , the maximum kinetic energy of emitted electrons will be Given E (in eV ) = 1237 λ(in nm) (1) 4.5 eV (2) 3.0 eV (3) 1.5 eV (4) 15.1 eV
What This Question Tests
A straightforward application of Einstein's photoelectric equation to calculate the maximum kinetic energy of emitted electrons using the incident wavelength and threshold wavelength.
Concepts Tested
Formulas Used
K_max = hν - φ
φ = hc/λ_threshold
E = hc/λ (given E in eV, λ in nm as E = 1237/λ)
📚 NCERT Sections This Tests
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?
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?
11.8 — 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
- 2019
- Shift
- 10 Apr Shift 1
- Q Number
- Q26
- Type
- MCQ
- NCERT Ref
- Class 12 Physics Ch 11: Dual Nature of Matter
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