Energy levels and photon emission (AQA A-Level Physics): Flashcards

By passing light from a fluorescent tube through a diffraction grating

Contains discrete wavelengths only, not continuous

Quantised energy levels in atoms

By passing white light through a cooled gas

Energy differences between atomic energy levels

$\Delta E = E_1 - E_2$

$hf = E_1 - E_2$

Planck's constant

Frequency of the photon

$1.6 \times 10^{-19}$ J