# How to express the mass of a proton and an elektron in MeV/c²? Thank you!

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I know how to express something in MeV/u and I know how much c² is... But i can't make up my mind how to do this?

I know how to express something in MeV/u and I know how much c² is... But i can't make up my mind how to do this?

##### 1 Answer

May 31, 2018

This is a bit sneaky - it’s physics shorthand, that’s all.

#### Explanation:

As you know mass and energy are inter-convertible (

This means that physicists often express the masses or energies of subatomic particles in eV, but of course if we rearrange the first equation for mass we get

Sorry.