Confused conceptually with photoelectric effect

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LeannaPhan14BDis1D
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Confused conceptually with photoelectric effect

Postby LeannaPhan14BDis1D » Thu Oct 11, 2018 10:11 pm

I do not understand when Lavelle spoke on the length of the wavelength and how it ejects electrons. Please advice since the reading makes it only slightly less confusing. I get how the shorter the wavelength is it will eject more electrons, but I do not understand how. Thank you.

Chem_Mod
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Re: Confused conceptually with photoelectric effect

Postby Chem_Mod » Thu Oct 11, 2018 10:26 pm

The photoelectric effect refers to the emission of electrons when photons of light shine on a metal surface. Essentially, photons of light transfer the energy they carry to electrons they contact, and depending on how much energy is transferred, the electrons can absorb the energy, be emitted, and leave the metal the light was shown on. The minimum energy required to emit an electron from a metal refers to the metal's work function, or . If the energy of a photon that contacts an electron happens to be lower than the metal's work function, then the electron will not be released. If the energy of a photon that contacts an electron happens to equal the metal's work function, then the electron will be released, but have no kinetic energy. If the energy of a photon that contacts an electron happens to exceed this work function, then the electron will be released and have kinetic energy. Based on the concepts here, it makes sense that the equation is as follows: Ephoton of light = + KEelectron emitted.

melodyzaki2E
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Re: Confused conceptually with photoelectric effect

Postby melodyzaki2E » Thu Oct 11, 2018 10:27 pm

I think he was just trying to get the fact that the length of the wavelength is inversely related to the frequency of the photons, so long wavelengths didn't have enough energy to allow electrons to escape the metal but short wavelengths had high frequency so they were able to excite the electrons in the metal enough to allow them to escape. I don't know if that totally makes sense or if that was what you were confused about but hope it helped.

Douglas Nguyen 2J
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Re: Confused conceptually with photoelectric effect

Postby Douglas Nguyen 2J » Thu Oct 11, 2018 10:45 pm

For the photoelectric effect, a shorter wavelength means a higher frequency. Higher frequency equates to a greater amount of energy in the photon, and thus, an electron is ejected because sufficient energy was provided. E=hv


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