COMEDK · Physics · 28. Atomic Physics
A hydrogen atom absorbs energy and rises to n = 3 state from its ground state n = 1. If the potential energy of the atom at its ground state is -13.6eV, find the wave length emitted by it when it returns to its ground state:
{Planck's constant= \(6.6 \times 10^{34}\) J s}
- A \(7000\)Å
- B \(1020\)Å
- C \(12000\)Å
- D \(4000\)Å
Answer & Solution
Correct Answer
(B) \(1020\)Å
Step-by-step Solution
Detailed explanation
Total energy of hydrogen atom in ground state, \(E_1 = -13.6\) eV Energy in \(n=3\) state, \(E_3 = \dfrac{-13.6}{3^2} = -1.51\) eV Energy of emitted photon, \(\Delta E = E_3 - E_1 = -1.51 - (-13.6) = 12.09\) eV Wavelength of emitted photon, \(\lambda = \dfrac{hc}{\Delta E}\)…
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