Nuclear & Particle Physics - Hydrogen

The energy levels of the hydrogen atom are given in terms of the principal quantum number n and a positive constant A by the expression 

A. A(n + ½)
B. A(1 − n²)
C. A(¼ + 1/n)
D. An²
E. −A/n²

(GR8677 #19 )

Solution:

Energy level of hydrogen atom: E_n = −13.6/n² eV

Answer: E