If we shine a light that has less energy than the work function energy of the electron of an atom on a metal, the electron is not released but excited and electron gives off this excess energy as heat or collisions or light.
We know that the intensity of incoming light does not affect whether the electron will be released from the metal or not, only the energy of the incoming photon determines it. So,
Assume that we hit an electron with an energy lower than the work function energy so that the electron gets excited and builds up with energy.
WHAT IF Before that excited electron releases its build -up energy as heat or light or collisions we hit it again with a light that again has an energy lower than work function energy, why isn't it released from the metal?
