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eV? (1 Viewer)

v1

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can somebody explain what eV is?
i don't really understand why it is the unit of maximum kinetic energy of electron
 

jenslekman

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1eV = 1.6 x 10^-19 J

so it is basically another way of expressing energy ... hence kinetic energy of an electron...

the reason why we use eV is for the stopping voltage experiment (JJ thomson experiment i believe). in this experiment a voltage is applied to oppose the photoelectric current, and the voltage when the net current reaches zero is the stopping voltage (in eV). Since current is just a measure of the kinetic energy of an electron, the stopping voltage is the maximum kinetic energy of the electron.
 

IamBread

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As stated above, 1eV = 1.6 x 10^-19 J

eV stands for electronvolt, it's just another unit of energy, but it is related to an electron. You could use joules, it doesn't matter.
 

oompaman

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1eV = 1.6 x 10^-19 J

so it is basically another way of expressing energy ... hence kinetic energy of an electron...

the reason why we use eV is for the stopping voltage experiment (JJ thomson experiment i believe). in this experiment a voltage is applied to oppose the photoelectric current, and the voltage when the net current reaches zero is the stopping voltage (in eV). Since current is just a measure of the kinetic energy of an electron, the stopping voltage is the maximum kinetic energy of the electron.
Why in eV? why not V?
 

Fizzy_Cyst

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Stopping voltage is measured in V, not eV!

1eV = work required to 'push' an electron through a potential difference of 1V

From W = qV
 

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