Q17.The radiation corresponding to 3 →2 transition of a hydrogen atom falls on a gold surface to generate photoelectrons. These electrons are passed through a magnetic field of 5 × 10−4 T. Assume that the radius of the largest circular path followed by these electrons is 7 mm, the work function of the metal is: (Mass of electron = 9. 1 × 10−31 kg) (1) 1. 36 eV (2) 1. 88 eV (3) 0. 16 eV (4) 0. 82 eV
What This Question Tests
This question integrates concepts from Bohr's atomic model (photon energy), photoelectric effect (work function and KE of electrons), and magnetic effects (radius of path), requiring multiple calculations to find the work function.
Concepts Tested
Formulas Used
E_n = -13.6/n² eV
E_photon = E_initial - E_final
KE_max = E_photon - Φ
r = mv/(eB)
KE = (1/2)mv²
📚 NCERT Sections This Tests
12.5 — A Hydrogen Atom Initially In The Ground Level Absorbs A Photon,
Physics Class 12 · Chapter 12
12.5 A hydrogen atom initially in the ground level absorbs a photon, which excites it to the n = 4 level. Determine the wavelength and frequency of photon.
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?
12.3 — A Difference Of 2.3 Ev Separates Two Energy Levels In An Atom. What
Physics Class 12 · Chapter 12
12.3 A difference of 2.3 eV separates two energy levels in an atom. What is the frequency of radiation emitted when the atom make a transition from the upper level to the lower level?
📋 Question Details
- Chapter
- Dual Nature of Matter
- Topic
- Photoelectric effect and Bohr's model
- Year
- 2021
- Shift
- 20 Jul Shift 1
- Q Number
- Q17
- Type
- Multi concept
- NCERT Ref
- Class 12 Physics Ch 11: Dual Nature of Radiation and Matter, Class 12 Physics Ch 12: Atoms
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