Topic : bohr’s model for hydrogen atom

Angular momentum of electron in 3rd stationary orbit of hydrogen atom is

The ratio of the wavelengths of the light absorbed by a Hydrogen atom when it undergoes n = 2 → n = 3 and n = 4 → n = 6 transitions, respectively, is

Energy and radius of first Bohr orbit of He⁺ and Li²⁺ are [Given R_H = 2.18×10⁻¹⁸ J, a₀ = 52.9 pm]

Which of the following electronic transition from 5th orbit of He$^+$ ion spectrum will have maximum frequency?

The angular momentum of electron in 3rd orbit of H-atom is