JEE Mains · Physics · STD 12 - 12. atoms
Speed of an electron in Bohr's \(7^{\text {th }}\) orbit for Hydrogen atom is \(3.6 \times 10^6\,m / s\). The corresponding speed of the electron in \(3^{\text {rd }}\) orbit, in \(m / s\) is \(........\times 10^6\)
- A \(1.8\)
- B \(7.5\)
- C \(3.6\)
- D \(8.4\)
Answer & Solution
Correct Answer
(D) \(8.4\)
Step-by-step Solution
Detailed explanation
\(V _{ n } \propto \frac{ Z }{ n }\) \(Z =1, \therefore V _{ n } \propto \frac{1}{ n }\) \(\therefore \frac{ V _3}{ V _7}=\frac{7}{3}\) \(\therefore V _3 =\frac{7}{3} V _7\) \(=\frac{7}{3} \times 3.6 \times 10^6\,m / s\) \(=8.4 \times 10^6\,m / s\)
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