MedVision ad

eV? (1 Viewer)

v1

Active Member
Joined
Jun 9, 2012
Messages
219
Gender
Undisclosed
HSC
2012
can somebody explain what eV is?
i don't really understand why it is the unit of maximum kinetic energy of electron
 

jenslekman

Member
Joined
Oct 11, 2011
Messages
290
Gender
Male
HSC
2012
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

Member
Joined
Oct 24, 2011
Messages
757
Location
UNSW
Gender
Male
HSC
2011
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

Member
Joined
Apr 29, 2012
Messages
85
Gender
Undisclosed
HSC
N/A
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

Well-Known Member
Joined
Jan 14, 2011
Messages
1,213
Location
Parramatta, NSW
Gender
Male
HSC
2001
Uni Grad
2005
Stopping voltage is measured in V, not eV!

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

From W = qV
 

Users Who Are Viewing This Thread (Users: 0, Guests: 1)

Top