Explain intensity in the photoelectric effect (detailed)

A detailed presentation to aid explanation of the role of radiation intensity in the photoelectric effect for various photon frequencies relative to the threshold frequency of the metal. Students often misunderstand the inability of increased intensity to trigger the photoelectric effect and therefore believe it has no role. This presentation is a visual aid to help the teacher show that it has a role in controlling the number of photons arriving per unit time.

This presentation compares low and high intensity sources of red and green light with low and high intensity blue light (where green and blue light have frequencies above the threshold frequency). The effect of intensity on the number of photons arriving at the metal is made clear and intensity is clearly distinguished from photon energy.

This is a Keynote presentation (macOS, iPadOS and iOS).

Useful for all A-Level physics specifications.

The photoelectric effect is an important experiment in physics that proves that light behaves like a particle, it was a founding experiment for quantum theory. Einstein won his Nobel prize for his work on explaining the photoelectric effect.