Science Project on the Photoelectric Effect

[beatlemaniacj]

I am doing a science project on the photo electric effect (the experiment is the correlation between frequency, intensity, and electrons released.) My one problem is that I need some way to measure the free electrons. I was thinking a simple circuit with an anode plate and a cathode plate with an electrical field between the two, hooked up to an electrometer. The free electrons produced would get attracted to the cathode and would affect the reading of the electrometer. Does this sound like a viable experiment?

 

[NascentOxygen]

You would need to do it in a vacuum.

 

[Bobbywhy]

beatlemaniacj,

I suggest you study the photoelectric effect first, and then decide on your science project. Here are two sites you can visit to get started. Also, check out the Hammatsu Handbook...it is an excellent guide to the correlations between frequency, intensity, etc. Good luck!

Bobbywhy

 

[beatlemaniacj]

I know about the photoelectric effect. This is for a school science fair. I thought it would be an interesting project. As for the vacuum, wouldn't the electrostatic attraction propel the particles?

 

[Bobbywhy]

NascentOxygen is correct: You will need a vacuum. Electrons will not pass easily through air. You are correct: electrostatic potential can attract and move electric charges through air. Just experiment with a Van de Graf generator. You can charge up an object across a large air gap. But that would NOT demonstrate the photoelectric effect. But, of course, you already know about that.

 

[Bobbywhy]

Oops, I forgot to include a few references in an earlier post about your project. Excuse my forgetfulness. Below are three sites that you may find useful. The first two are technical explanations with descriptions of the science behind the photoelectric effect. But since you say you already know about the photoelectric effect you may just ignore them. The third one is an example of a real project similar to the one you are proposing.

http://en.wikipedia.org/wiki/Photomultiplier
http://en.wikipedia.org/wiki/Work_function
http://www.education.com/science-fair/article/photoelectric-effect/

 

[beatlemaniacj]

My experiment involves parallel plates. Some of the electrons, hopefully will get attracted to the anode and register on the voltmeter. Not all of them need to. Just to show the ratios and such.