MHT CET · Physics · Atomic Physics
The kinetic energy of the electron in an orbit of radius \(r\) in hydrogen atom is proportional to ( \(e=\) electronic charge \()\)
- A \(\frac{e^2}{4 r}\)
- B \(\frac{e^2}{2 r}\)
- C \(\frac{e^2}{r}\)
- D \(\frac{e^2}{2 r^2}\)
Answer & Solution
Correct Answer
(B) \(\frac{e^2}{2 r}\)
Step-by-step Solution
Detailed explanation
The potential energy of the electron in the nth orbit of radius \(r\) in Hatom, \(U=\frac{e^2}{r}\) (in CGS)
\(\because\) K.E. \(=\frac{1}{2} \mid\) P.E. \(\mid \Rightarrow K=\frac{e^2}{2 r}\)
\(\because\) K.E. \(=\frac{1}{2} \mid\) P.E. \(\mid \Rightarrow K=\frac{e^2}{2 r}\)
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