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JEE Mains · Physics · STD 12 - 12. atoms
The radius of electron's second stationary orbit in Bohr's atom is \(R\). The radius of the third orbit will be
- A \(3 R\)
- B \(2.25 R\)
- C \(9 R\)
- D \(\frac{R}{3}\)
Answer & Solution
Correct Answer
(B) \(2.25 R\)
Step-by-step Solution
Detailed explanation
(b) \( r \propto {n^2}\) ==> \(\frac{{{r_{(n = 2)}}}}{{{r_{(n = 3)}}}} = \frac{4}{9}\) ==> \({r_{(n = 3)}} = \frac{9}{4}R = 2.25\,R\)
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