The speed of electron is given by v=2.18×106×nZms−1, where, Z is atomic number and n is number of orbit.
Now, for third orbit, ratio of speed of electron is vHe+vH=ZHe+ZH=21
⇒vHvHe+=12
JEE Main 2022 — Physics Modern Physics
The ratio for the speed of the electron in the 3rd orbit of He+ to the speed of the electron in the 3rd orbit of hydrogen atom will be :
Held on 25 Jun 2022 · Verified 6 Jul 2026.
1:1
1:2
4:1
2:1
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