The angular momentum of an electron in the fourth orbit of He⁺ is 4.22 × 10⁻³⁴ J s. What is the frequency of the photon
n=4. ΔE ≈ 1.635×10⁻¹⁸ J. ν ≈ 2.467×10¹⁵ Hz.
Ref: NCERT Class 11 Chemistry > Chapter 2: Structure of Atom > Topic: Quantum Numbers - Principal Azimuthal Magnetic Spin