B Potassium or other minerals and the photoelectic effect

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Would UVC shined onto Potassium cause it to emanate more electrons than its specific work function? Does only the specific work function per mineral cause the mineral to emanate electrons or more energetic sources can also cause it to do the same without using its specific work function?
 

sophiecentaur

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Would UVC shined onto Potassium cause it to emanate more electrons than its specific work function? Does only the specific work function per mineral cause the mineral to emanate electrons or more energetic sources can also cause it to do the same without using its specific work function?
It's not clear from your question, what your existing level of knowledge is. Potassium is a metal and not a 'mineral'. Is your question a general one or is it particularly related to UVC?
The work function is just the minimum photon energy needed to release a photoelectron from the very surface atoms of a metal. It's a threshold value of energy. It is not an 'on-off' process and higher energy photons will be able to cause more photoelectrons to be emitted - there will be a progressive increase in photocurrent for a constant rate of photons arriving as the frequency increases.
Photons with higher energy will result in faster photoelectrons or, for high enough energy, will release tighter bound electrons which may result in more than just one electron being released
 
This was in regards to whether a metal can emanate more electrons from a higher energetic UVC emitter.

Whats the rate of electrons emmited and at which velocity from a 3^2cm potassium surface area from a typical 8w mercury enclosed in quartz UVC emitter? Supposing the lamp would be 2-3 inches away from the metal.
 

sophiecentaur

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Whats the rate of electrons emmited and at which velocity from a 3^2cm potassium surface area
From what the text books tell us, the Potassium surface needs to be clean - for the purposes of measuring work function. The standard apparatus has a blade inside the vacuum which scrapes the metal surface. (See any A Level txt book.)
You haven't described the context of this. Are you trying to make a calibrated detector? Why would you DIY the thing when there must be such things available.
 

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