JEE Mains · Physics · STD 12 - 12. atoms
Consider an electron in a hydrogen atom, revolving in its second excited state (having radius \(4.65\, \mathop A\limits^o \)). The de-Broglie wavelength of this electron is....\(\mathop A\limits^o \)
- A \(12.9\)
- B \(9.7\)
- C \(6.6\)
- D \(3.5\)
Answer & Solution
Correct Answer
(B) \(9.7\)
Step-by-step Solution
Detailed explanation
\(2 \pi r_{n}=n \lambda_{n}\) \(\lambda_{3}=\frac{2 \pi\left(4.65 \times 10^{-10}\right)}{3}\) \(\lambda_{3}=9.7 \mathrm{A}\)
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