An excited atom has three energy levels at ,

PHYSICS · Single correct · A Level · Physics · Particles and radiation · Particles and radiation

Problem

An excited atom has three energy levels at

E_1=-10\,\text{eV}

E_2=-5.0\,\text{eV}

, and

E_3=-2.0\,\text{eV}

. When the atom makes a transition from the

n=3

level to the

n=2

level, it emits a single photon. What is the wavelength of the emitted photon? (Use

hc = 1240\,\text{eV}\cdot\text{nm}

.) (a)

155\,\text{nm}

(b)

620\,\text{nm}

(c)

410\,\text{nm}

(d)

248\,\text{nm}