## Spectroscopy experimenting

$E=hv$

rkang00
Posts: 69
Joined: Fri Sep 28, 2018 12:25 am

### Spectroscopy experimenting

in a spectroscopy experiment, there are three components: E = hv, work function, and Ek. If the electron has no kinetic energy, does it mean that the electron is detached but doesn't move? How would it look like in real life?

Rian Montagh 2K
Posts: 60
Joined: Fri Sep 28, 2018 12:15 am

### Re: Spectroscopy experimenting

I think you're referring to the photoelectric effect, where light is shined on a metal to eject electrons to see how much energy is needed to do so. Spectroscopy is the analysis of light emitted or absorbed by a substance with a spectrometer (you analyze the specific wavelengths/spectral lines). For the electron with no kinetic energy, the electron is detached but it can still move if it's affected by positive or negative charges. For example, in the photoelectric experiments, the detector has a positive charge so the zero kinetic energy electrons are attracted to the detector and can still be recorded.

505095972
Posts: 69
Joined: Fri Sep 28, 2018 12:17 am

### Re: Spectroscopy experimenting

This is confusing to me too... Do you mean that if there is energy absorbed from the light by the metal that is exactly the same as the work function, the electrons are excited but remain with the metal rather than being ejected?

Rian Montagh 2K
Posts: 60
Joined: Fri Sep 28, 2018 12:15 am

### Re: Spectroscopy experimenting

I read more about what happens when the photon energy equals the threshold energy and one thing I found is that that electron with zero kinetic energy could fall back to the metal and release a photon the same as that one that emitted the electron in the first place.

Elena Saab 4A
Posts: 43
Joined: Fri Sep 28, 2018 12:27 am

### Re: Spectroscopy experimenting

I believe that if the energy of the photon = the threshold frequency, there is enough energy to remove an electron but not enough to give it a velocity. however, if the energy of the photon is greater than the frequency, the electron would have kinetic energy.