An electron in an atom transitions from an energy level at to a lower level at

PHYSICS · Subjective · A Level · Physics · Particles and radiation · Particles and radiation

Problem

An electron in an atom transitions from an energy level at

-2.0\,\text{eV}

to a lower level at

-5.0\,\text{eV}

. Calculate the wavelength of the photon that is emitted, in nanometres. Express your answer to two significant figures. Constants:

h = 6.63\times10^{-34}\,\text{J}\cdot\text{s}

c = 3.00\times10^{8}\,\text{m/s}

1\,\text{eV} = 1.60\times10^{-19}\,\text{J}