JEE Mains · Physics · STD 12 - 12. atoms
The radius of electron's second stationary orbit in Bohr's atom is \(R\). The radius of \(3 rd\) orbit will be \(.........R\)
- A \(\frac{1}{3}\)
- B \(2.25\)
- C \(3\)
- D \(9\)
Answer & Solution
Correct Answer
(B) \(2.25\)
Step-by-step Solution
Detailed explanation
\(r =0.529 \times \frac{ n ^2}{ z }\) \(r \propto n ^2\) \(R \propto(2)^2\) \(R _1 \propto(3)^2\) \(\frac{ R _1}{ R }=\frac{4}{9}\) \(R _{ l }=\frac{9 R }{4}\) \(R _1=2.25 R\)
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