1ev electron volt

Electron volt is a unit of energy. 

Can also be use as work

Use to measure small energy and work

Defination of 1ev?

1 ev is the amount of kinetic energy gained or lost by a single electron accelerating from rest through an electric potential difference of 1 volt in vaccum. 

Relation between ev and joule:

1 ev = 1 volt x  charge of one Electron = 1volt x 1.602x10^-19 coulombs

So, 1 ev = 1.602 x 10^-19 joule

The numerical value of 1 ev in joule is equivalent to the numerical value of the charge of an electron in coulomb's. 

Similarly, 1 joule = 6.242 x 10^18 ev

Some bigger unit is Mev

1Mev = 10^6 ev