JEE Mains · Physics · STD 12 - 12. atoms
The ratio for the speed of the electron in the \(3^{ rd }\) orbit of \(He ^{+}\)to the speed of the electron in the \(3^{\text {ad }}\) orbit of hydrogen atom will be
- A \(1: 1\)
- B \(1: 2\)
- C \(4: 1\)
- D \(2: 1\)
Answer & Solution
Correct Answer
(D) \(2: 1\)
Step-by-step Solution
Detailed explanation
\(v \propto \frac{Z}{ n } \propto Z ( n = constant )\) \(\Rightarrow \frac{ V _{ He ^{+}}}{ v _{ H }}=\frac{ Z _{ He ^{+}}}{ Z _{ H }}=\frac{2}{1}\)
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