The Quantum World

[Mohamed Mido]

If the energy of the photon is exactly the same as the energy needed to remove the electron, does the electron never leave the surface of the metal because there is no excess energy and therefore no kinetic energy?

[Summer_Corona 3L]

I believe the electron can still be ejected. I have in my notes from lecture that as long as the energy of the photon is greater than or equal to the work function, then the electron will be emitted.

[Lauren Sarigumba 1K]

The electron still gets emitted if the energy of the light matches the energy of the work function. The kinetic energy would just be zero.

[Lillian]

I think maybe the electron wouldn't really move from the surface, but it would still be physically separated from the other atoms/electrons (it wouldn't be bound). Then again, that's a pretty rare scenario, for the energy of the photon to match the threshold energy exactly haha :DD

[Danielle Goldwirth 3F]

That's a good question and I believe the answer is revealed in your question: you say that the energy of the photon would be exactly the same as the energy needed to remove the electron, so wouldn't this imply that the electron is ejected because it received the EXACT amount NEEDED to REMOVE it from the surface. Based on this logic, I would assume that the electron is ejected, but I am not completely sure.

[Bella Bursulaya 3G]

I believe in an experiment, there is a machine that has a positive charge that will attract that electron to it. However, in real life, if the electron doesn't have any excess kinetic energy, it would be removed from the atom temporarily and then reabsorbed as it is pulled by the positive charge of the nucleus.

[Jaden Kwon 3C]

Does anyone know how an electron can be emitted with 0 kinetic energy? Does it just stay in place or is it something else.

[Joanna Huang]

According to my notes, the electron can still be ejected from the surface of the metal if the photon energy is equal to the energy needed to eject the electron from the metal.