Select the correct statement(s) regarding the photoelectric effect. The photoelectric effect is not observed when each photon has an energy less than the work function. The work function is the energy required to remove an electron from a metal, (Kind of like an ionization energy) The energy of an incident photon equals the sum of the work function and the kinetic energy carried away by an ejected electron. The type of radiation that stimulates the photelectric effect is usually infrared light. Any frequency radiation can cause the photoelectric effect, but it is more pronounced at higher frequencies