For hydrogen like atom, the velocity of electron in nth orbit is given by
v=2ϵ0hnz2e2
∴v∝n1
⇒v2v1=n1n2
⇒v23.6×106=73
v2=8.4×106ms−1
Speed of an electron in Bohr’s 7th orbit for Hydrogen atom is 3.6×106ms−1. The corresponding speed of the electron in 3rd orbit, in ms−1 is :
Held on 30 Jan 2023 · Verified 6 Jul 2026.
1.8×106
7.5×106
3.6×106
8.4×106
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