AP EAMCET · PHYSICS · Atomic Physics
The ratio of speed of electrons in the first excited state of hydrogen atom to the speed of light in vacuum is [Given, Planck's constant \(=6.625 \times 10^{-34} \mathrm{Js}\) and permittivity of free space is \(8.85 \times 10^{-12} \mathrm{Fm}^{-1}\) ]
- A \(5 \times 10^{-3}\)
- B \(7.3 \times 10^{-3}\)
- C \(3.6 \times 10^{-3}\)
- D \(36.5 \times 10^{-3}\)
Answer & Solution
Correct Answer
(C) \(3.6 \times 10^{-3}\)
Step-by-step Solution
Detailed explanation
Velocity of electron in the nth orbit of an atom is given by \(v=\frac{2 \pi k e^2}{h} \times \frac{Z}{n}\) where, \(\frac{2 \pi k e^2}{h}\) is a constant quantity and \(\mathrm{Z}\) is atomic number. Hence, speed of electron in first excited state (n = 2) is…
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