Physics
Ground State Energy in Atomic Physics
Quick fact
The ground state energy of a hydrogen atom is -13.6 electron volts (eV). This negative value means the electron is bound to the nucleus, and this precise number determines the color of light hydrogen emits when excited.
Why this is interesting
You know that atoms are stable—they don’t randomly collapse or explode. But what keeps an atom’s electron from falling into the nucleus? The answer lies in its least possible energy, call the 'ground state'.