The ratio of the angular momentum of an electron in the third orbit of H to the second orbit of He⁺ is: (h = 6.626 × 10⁻
L₃(H)/L₂(He⁺) = 3/2 = 1.5.
Ref: NCERT Class 11 Chemistry > Chapter 2: Structure of Atom > Topic: Atomic Models - Thomson Rutherford and Bohr Model