Thu July 12, 2012 By: Tejit Pabari

why is an electron emitted when a light ray is incident on a metal (i.e. when photoelectric effect occurs

Expert Reply
Sat July 14, 2012
Each material has a work function, i.e. the minimum energy required by an electron to get itself enough excited so that it can be freed from the interactions with atom andsurroundings.
SO in this case that energy is provided by the light ray incident on it.
Ask the Expert