Q27.The radiation corresponding to 3 →2 transition of hydrogen atom falls on a metal surface to produce photoelectrons. These electrons are made to enter a magnetic field of 3 × 10−4 T. If the radius of the largest circular path followed by these electrons is 10.0 mm, the work function of the metal is close to : (1) 1.8 eV (2) 1.1 eV (3) 0.8 eV (4) 1.6 eV
What This Question Tests
This is a multi-concept problem requiring calculations from atomic structure (photon energy), photoelectric effect (kinetic energy), and motion in a magnetic field (maximum kinetic energy), with unit conversions.
Concepts Tested
Formulas Used
E_photon = 13.6 Z² (1/n₁² - 1/n₂²) eV
E_photon = Φ + K_max
K_max = (qBr)² / (2m)
📚 NCERT Sections This Tests
12.7 — The Radius Of The Innermost Electron Orbit Of A Hydrogen Atom Is
Physics Class 12 · Chapter 12
12.7 The radius of the innermost electron orbit of a hydrogen atom is 5.3×10–11 m. What are the radii of the n = 2 and n =3 orbits?
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?
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.
📋 Question Details
- Chapter
- Dual Nature of Matter
- Topic
- Photoelectric effect and Bohr model
- Year
- 2014
- Shift
- 06 Apr
- Q Number
- Q27
- Type
- Multi concept
- NCERT Ref
- Class 12 Physics Ch 11: Dual Nature of Matter and Radiation; Ch 12: Atoms; Class 12 Physics Ch 4: Moving Charges and Magnetism
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