Q30.When a hydrogen atom going from n = 2 to n = 1 emits a photon, its recoil speed is x5 m s−1 . Where x = _______. (Use: mass of hydrogen atom = 1. 6 × 10−27 kg , charge of electron e = 1. 6 × 10−19 C)
What This Question Tests
This multi-concept question combines the Bohr model for hydrogen atom energy levels with photon emission and the principle of conservation of momentum to find the recoil velocity of the atom.
Concepts Tested
Formulas Used
E_n = -13.6/n^2 eV
E_photon = hc/λ = ΔE
p = E_photon / c
p_atom = p_photon
📚 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.
12.6 — (A) Using The Bohr’S Model Calculate The Speed Of The Electron In A
Physics Class 12 · Chapter 12
12.6 (a) Using the Bohr’s model calculate the speed of the electron in a hydrogen atom in the n = 1, 2, and 3 levels. (b) Calculate the orbital period in each of these levels.
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?
📋 Question Details
- Chapter
- Atoms
- Topic
- Bohr Model and Recoil of Atom
- Year
- 2024
- Shift
- 29 Jan Shift 1
- Q Number
- Q30
- Type
- Numerical
- NCERT Ref
- Class 12 Physics Ch 12: Atoms
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