Explain Hertz's observation in short.

(N/A) The photoelectric effect was first observed by the scientist $Hertz$.
$Hertz$ conducted an experimental investigation into the production of electromagnetic waves using spark discharges.
$Hertz$ observed that high-voltage sparks across a detector loop were enhanced when the emitter plate was illuminated by ultraviolet light from an arc lamp.
When light is incident on a metal surface,some electrons near the surface absorb enough energy from the incident radiation to overcome the attraction of positive ions within the metal.
After gaining sufficient energy from the incident light,these electrons escape from the surface of the metal into the surrounding space.