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### work function

Posted: Mon Oct 08, 2018 6:20 pm
What is the work function? For example, in the equation E = hv + work function.

### Re: work function

Posted: Mon Oct 08, 2018 6:26 pm
The term "work" is a physics term. Work refers to the amount of kinetic energy it takes to complete a task. For example, it might take 1 joule of work to lift an apple one meter off the ground. In this context though, I'm pretty sure the work equation is the "phi" symbol that Professor Lavelle used to signify the minimum energy it takes to eject the electron from the metal surface.

### Re: work function

Posted: Wed Oct 10, 2018 4:44 pm
The work function is also called the "threshold energy", so watch for that too! The way I remember how the threshold energy function is by relating it in my mind as something similar to "activation energy" because in both cases, if the minimum requirement is not met, then nothing will occur. To elaborate in this context, if the energy of the photon is NOT at least equal to or greater than the work function (aka threshold energy), then e- will not be removed.

### Re: work function

Posted: Wed Oct 10, 2018 5:08 pm
Professor Lavelle connected the word "work function" to "threshold energy" -- in other words, the minimum energy needed to eject an electron. In class he made an anology to a cross country team that was unable to jump a hurdle and therefore did not advance any further in the race. This is related to when the threshold energy requirement is not met and therefore the electrons are unable to be ejected until that requirement is at least met.

### Re: work function

Posted: Thu Oct 11, 2018 6:00 pm
Basically, the work function (threshold energy) is going to be equal to the energy of the photon (hv) minus the kinetic energy of the electron upon removal (excess energy). Of course, if the threshold energy is not equal to or less than the energy of the photon, then the electron will not be removed in the first place.