The radius of the third orbit of a hydrogen atom is 4.761 × 10⁻¹⁰ m. What is the angular momentum of an electron in the
L = nh/2π, for n=5, L = 5 × 6.626×10⁻³⁴ / (2×3.14) = 5.275×10⁻³⁴ J s.
Ref: NCERT Class 11 Chemistry > Chapter 2: Structure of Atom > Topic: Shapes of Orbitals - s p d f and Nodes and Radial Probability