It would be logical to think that the more electrons are ejected from an atom, the harder it is to eject more.
I just learned about photoelectric effect experiment. The book is kinda telling me the threshold frequency never changes even as more and more electrons are ejected.
But it is very counterintuitive because 1. Screening effect is reduced, meaning stronger nuclear attraction, more force, more energy required to ionize that electron. 2. Because the atom is now ionized, there is then electrostatic force between the atom and any electron attempting to get out.