Transcript The electron-volt - Hockerill Students

The electron-volt: eV
“energy gained by an electron
moving through an electric
potential difference of one volt.
(OR: Work done moving an
electron through an electric
potential difference of one volt.)”
Situations: eV
An electon passing through a resistor across
which there is a potential difference of 3V
(3 eV of thermal energy transferred to the R)
An electron passing though a generator that is
generating an e.m.f of 24V.
(24 eV of Ep transferred to the e-)
An electron accelerates across a
9V electric field (9eV of Ek)
How much energy?
1 Volt is 1 Joule per coulomb.
An electron has a charge of 1.6 x 10-19 coulombs
So 1eV is 1.6 x 10-19 Joules
In a coulomb of charge there are therefore:
1/ 1.6 x 10-19 electrons = 6.25 x 10+18 electrons.
So 1 Joule is 6.25 x 10+18 eV