Concepts Of Physics MCQ Edition [Volume 2]PhysicsBohr's Model and Physics of the Atom
When a photon is emitted by a hydrogen atom, it carries momentum. Calculate the momentum carried by the photon if a hydrogen atom emits light of wavelength 656.3 nm .
Options
- A3.3 10⁻²⁷ kg m s ⁻¹
- B2.0 10⁻²⁷ kg m s ⁻¹
- C1.0 10⁻²⁷ kg m s ⁻¹
- D1.0 10⁻¹⁹ kg m s ⁻¹
Correct answer
C. 1.0 10⁻²⁷ kg m s ⁻¹
Step-by-step solution
The momentum of a photon is given by the de Broglie relation: p = h Given: Wavelength = 656.3 nm = 656.3 10⁻⁹ m Planck's constant h = 6.63 10⁻³⁴ J s Substituting the values: p = 6.63 10⁻³⁴ 656.3 10⁻⁹ p = 6.63 6.563 10⁻²⁷ p 1.0 10⁻²⁷ kg m s ⁻¹