Q13.Radiation, with wavelength 6561 Å falls on a metal surface to produce photoelectrons. The electrons are made to enter a uniform magnetic field of 3 × 10−4 T . If the radius of the largest circular path followed by the electrons is 10 mm , the work function of the metal is close to: (1) 1.6 eV (2) 0.8eV (3) 1.1 eV (4) 1.8eV
What This Question Tests
This question integrates the photoelectric effect with the motion of a charged particle in a magnetic field, requiring the calculation of work function from maximum kinetic energy determined by the radius of the circular path.
Concepts Tested
Formulas Used
E = hc/λ
K_max = E - Φ
r = mv / (qB)
📚 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?
11.3 — 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?
11.2 — The Work Function Of Caesium Metal Is 2.14 Ev. When Light Of
Physics Class 12 · Chapter 11
11.2 The work function of caesium metal is 2.14 eV. When light of frequency 6 ×1014Hz is incident on the metal surface, photoemission of electrons occurs. What is the (a) maximum kinetic energy of the emitted electrons, (b) Stopping potential, and (c) maximum speed of the emitted photoelectrons?
📋 Question Details
- Chapter
- Dual Nature of Matter
- Topic
- Photoelectric effect
- Year
- 2020
- Shift
- 09 Jan Shift 1
- Q Number
- Q13
- Type
- Multi concept
- NCERT Ref
- Class 12 Physics Ch 11: Dual Nature of Radiation and Matter
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