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Dual Nature of Radiation and Matter — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsDual Nature of Radiation and Matter3 Marks
Question
  1. Using de Broglie's hypothesis, explain with the help of a suitable diagram, Bohr's second postulate of quantization of energy levels in a hydrogen atom.
  2. The ground state energy of hydrogen atom is - 13.6 eV. What are the kinetic and potential energies of the electron in this state?
✓

Answer

  1. $\lambda = \frac{\text{h}}{\text{p}} = \frac{\text{h}}{\text{mv}}$

$2\pi\text{r} = \text{n}\lambda$

$ =\text{n}\frac{\text{h}}{\text{mv}}$

$\Rightarrow\text{mvr} = \text{L} = \frac{\text{nh}}{2\pi}$

  1. Kinetic energy=13.6 eV

Potential energy = -27.2 eV.

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