Physics » Introduction to Quantum Physics » The Photoelectric Effect

# Summarizing the Photoelectric Effect

## Photoelectric Effect Summary

• The photoelectric effect is the process in which EM radiation ejects electrons from a material.
• Einstein proposed photons to be quanta of EM radiation having energy $$E=\text{hf}$$, where $$f$$ is the frequency of the radiation.
• All EM radiation is composed of photons. As Einstein explained, all characteristics of the photoelectric effect are due to the interaction of individual photons with individual electrons.
• The maximum kinetic energy $${\text{KE}}_{e}$$ of ejected electrons (photoelectrons) is given by $${\text{KE}}_{e}=\text{hf}\text{– BE}$$, where $$\text{hf}$$ is the photon energy and BE is the binding energy (or work function) of the electron to the particular material.

## Glossary

### photoelectric effect

the phenomenon whereby some materials eject electrons when light is shined on them

### photon

a quantum, or particle, of electromagnetic radiation

### photon energy

the amount of energy a photon has; $$E=\text{hf}$$

### binding energy

also called the work function; the amount of energy necessary to eject an electron from a material