What will be the angular momentum of an electron, if energy of this electron in H-atom is -1.5eV (in J-s)

Q: What will be the angular momentum of an electron, if energy of this electron in H-atom is -1.5 eV (in J-s)

(a) 1.05 × 10-34

(b) 2.1 × 10-34

(c) 3.15 × 10-34

(d) – 2.1 × 10-34

Ans: (c)