PRIDE CHEKERAnature of light. Centuries ago, Newton had proved that light is
corpuscular in nature, meaning particulate. He had discovered
primary colors of white light after passing the white light
through a prism. That was a milestone in the field of optics.
Since Newton's reign era there were no sophisticated machines
to test his theory, it was just accepted as true with that evidence
he had.
Ultraviolet catastrophe and photoelectric effect
In 20th century, a problem arose which shook the physics world.
The problem was known as the ultraviolet catastrophe. Thomas
Eddison invented the first bulb which was also a stimulus to a
theory of small things.
A bulb emitted infrared radiation, but physicists found it
difficult to produce ultraviolet light. Let me make this clear by
introducing you to the photoelectric effect experiment. Suppose
we have a gold leaf electroscope which is neutrally charged,
thus its leaf is collapse.
Take a metal or polythene made-rod and rub it on a surface, then
bring the rod proximity the plate of the gold leaf electroscope.
By rubbing the rod, you had statically charged it such that it is
now rich in electrons.
By bringing a negatively charged rod to a metal plate, you are