Question

What is photoelectric effect ? state it's observation ​

Answer 1

History of the Photoelectric Effect. Heinrich Hertz was the first to observe and publish observations about the photoelectric effect in 1887. He employed a spark gap, with an ultraviolet light source. He realized that if the light was partially blocked, sparks didn't occur as often.

Answer 2

The photoelectric effect is the emission of electrons or other free carriers when light falls on a material. Electrons emitted in this manner can be called photoelectrons. This phenomenon is commonly studied in electronic physics, as well as in fields of chemistry, such as quantum chemistry or electrochemistry.