T∝vr∝zn2×zn∝z2n3
T2T1=n23n13=81
T2=8T1
now,
f2=T21
f2=12.8×10−161≈7.8×1014
JEE Main 2020 — Physics Modern Physics
The time period of revolution of electron in its ground state orbit in a hydrogen atom is 1.6×10−16s. The frequency of revolution of the electron in its first excited state (in s−1 ) is:
Held on 7 Jan 2020 · Verified 6 Jul 2026.
1.6×1014
7.8×1014
6.2×1015
5.6×1012
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