Negative or Positive

[Mauricio Maravilla 3C]

When solving photoelectric effect problems, when is the energy of the atom negative or positive. I know it has to do something with going from lower to higher energy levels, vice versa.

[Ashlen Bullock 1H]

I do not think the photoelectric effect has to do with changing energy levels, as in electromagnetic radiation. The photoelectric effect is the emission of electrons when a light wave hits a surface. The energy of the outgoing electrons must be positive or zero because the energy of the incoming light has to be equal or greater to the threshold energy. Sorry if this is confusing.

[CesarLec1]

The photoelectric effect has to do when a photon comes into contact with electrons and either knocks them off or does not. Maybe you are thinking about when an e- goes down energy levels and the energy is negative as it was 0 prior to it going down.