Photons

[Kimberly Bauer 4E]

Can a photon ever NOT have enough energy to eject one e-, and if so what happens?

[Brandon Tao 1K]

Yes, it is possible for a photon to not have enough energy. If it does not then it won't be able to eject an electron. Like in lecture on Week 2, a photon packet overall does not need to have intense energy, but each photon itself must have enough intensity.

[Shimei_2F]

If a photon has less energy than the work function, it would not be able to eject electrons.

[Maya Pakulski 1D]

Yes, even if the photon has some energy, but not enough to get the electron the the next energy level, then the electron will not be ejected as it cannot go halfway between energy levels.

[Joanne Lee 1J]

Yes, there can be cases where the photons do not have enough energy to eject an electron. If there is not enough energy, then the electron will stay in whatever orbital it is currently in and will not jump to the other orbitals.

[Jorge Ramirez_4H]

How do photons affect an electron's momentum and position?

[Chetas Holagunda 3H]

In response to Jorge's question, if a photon has enough energy within it, it can interact with an electron which is on its path and then displace its position. It can affect its velocity because if the electron is put on a different trajectory, its distance it travels is changed, causing the velocity to change since velocity is a vector for distance/time.

[Katie Bart 1I]

And when velocity changes, so does momentum since velocity is a component of momentum.

[Brandon Tao 1K]

If a photon doesn't have enough energy(work function) to eject a photon then nothing will happen. The photon's energy will simply be absorbed by the electron but with no results or consequences.

[Jillian C 4C]

If a photon does not have enough energy to eject an electron, the electron stays in the same energy level.