Atoms & Nuclei

JEE Main level, single correct, medium

44 of 239

Question 44 of 239

The radius of third stationary orbit of electron for Bohr's atom is RR. The radius of fourth stationary orbit will be:

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Answer: (B) 169R\dfrac{16}{9}R

From Bohr's atomic model, it follows that
rn=n2Zr1...(1){r}_{n}=\dfrac{{n}^{2}}{Z}{r}_{1}...\left(1\right)
Following equation (1), it can be written that
r4r3=4232⇒r4=169R\dfrac{{r}_{4}}{{r}_{3}}=\dfrac{{4}^{2}}{{3}^{2}} \Rightarrow {r}_{4}=\dfrac{16}{9}R

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