PRIDE CHEKERAcharging the gold leaf, so that you will see the leaf angle
increasing as it diverges. This is due to electronic repulsions.
Now we want to discharge the leaf for it to collapse again.
Bring a bulb emitting infrared light and let the light beams hit
the leaf. Can you guess what will happen? Nothing! Nothing
will happen. Whatever the intensity of the infrared light emitted,
the leaf will not collapse.
Then let's try a bulb emitting ultraviolet light. Instantaneously,
when the ultraviolet light hit the leaf it collapses, despite its
intensity.
With this, Einstein concluded that, light is made of discrete
quanta of electromagnetic radiation, and these quanta packets
are called photons.
The infrared light photons had no ample energy to knock
electrons off the leaf, but the ultraviolet light photons had ample
energy to knock the electrons off the gold leaf, thus it collapses.
This energy is independent of the intensity of the light.
In a nutshell, Einstein had discovered that light is particulate in
nature, supporting Newton. And it was then it was found that,
that was why Ultraviolet light was difficult to produce because
great amount of energy was needed to make it than that needed
to make infra-red light.
The ultraviolet catastrophe was solved by the photoelectric
effect. The mechanism behind this had been discovered by Neil