I read if you increase the frequency then you can get the max kinetic energy and if you decrease the wavelengths you can get enough energy to knock the electron out of its atom of a gas. Is this true? How do you increase the frequency?
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$\begingroup$ Whats the setup you are talking about here? A moving photon hitting a stationary electron and then both flies off? If yes, look at Compton Scattering. $\endgroup$– sbpCommented Nov 17, 2017 at 12:50
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$\begingroup$ No the electron will be in a gas. So they wont be stationary. Sorry i didn't add that $\endgroup$– DeusIIXIICommented Nov 17, 2017 at 12:51
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$\begingroup$ You mean to say that you want to ionize the gas. In that case a high electric field will do the job for you. And high frequency of photon means going over to the ultravoilet side of the EM spectrum(ofcourse depending on your energy). $\endgroup$– sbpCommented Nov 17, 2017 at 12:54
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This is explained by Photo-electric effect. Einstein won the Nobel Prize for this.
According to Photo-electric effect, a photon with frequency greater than the threshold frequency(which is element specific) can knock off an electron out of its place.
The maximum Kinetic Energy will be $K.E = hv - hv_o$ where $v$ is frequency of incident photon and $v_o$ is the threshold frequency. $h$ is plank's constant. $hv_o$ is also called work function of the particular element.
The value of work function or threshold frequency of the element decides which incident photon frequency will knock the electrons out.
This increases when we move from metals to non metals.
About increasing the frequency, there are lab tools available to do it.
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1$\begingroup$ I was hearing a lot about photoelectric but didn't know what it meant. Was going to research it later. Thanks for letting me know im on the right track $\endgroup$ Commented Nov 17, 2017 at 13:26