Summary:
- German physicist Max Planck (1858-1947) studied the emission of light by hot objects.
- A quantum is the minimum quantity of energy that can either be lost or gained by an atom.
- Planck showed that the amount of radiant energy absorbed or emitted by an object is directly proportional to the frequency of the radiation.
- A small energy change results in the emission or absorption of low-frequency radiation.
- While the resulting energy may seem very small, this is for only one photon of light.
- Visible quantities of light consist of huge quantities of photons.