Define electron Volt and convert it into Joule unit.
Define electron Volt and convert it into Joule unit.
If an electron with charge $q=e=1.6 \times 10^{-19} \mathrm{C}$ is accelerated by a potential difference of 1 volt it would gain energy $=q \Delta \mathrm{V}$
$=1.6 \times 10^{-19} \times 1 \quad[\because \Delta \mathrm{V}=1 \mathrm{~V}]$
$=1.6 \times 10^{-19} \mathrm{~J}$
This unit of energy is defined as 1 electron volt or $1 \mathrm{eV}$.
Definition: "If an electron according through a potential difference of one volt the difference in potential (or kinetic) energy of an electron is known as one electron volt".
This unit are most commonly used in atomic, nuclear and particle physics.
Multiplier and submultiplier of $e \mathrm{~V}$ :
$1 \mathrm{meV}=1.6 \times 10^{-22} \mathrm{~J}$ $1 \mathrm{keV}=1.6 \times 10^{-16} \mathrm{~J}$ $1 \mathrm{MeV}=1.6 \times 10^{-13} \mathrm{~J}$ $1 \mathrm{GeV}=1.6 \times 10^{-10} \mathrm{~J}$ $1 \mathrm{TeV}=1.6 \times 10^{-7} \mathrm{~J}$
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