# Question about the Coulomb?

1. Feb 13, 2016

### Sam19KY

When we say "1 coulomb is equal to charge on 6.24 x 10^18 electrons" does "charge" mean elementary charge or simply -1 ?

2. Feb 13, 2016

### Staff: Mentor

$1C = 1As$, i.e. Coulomb is defined by Ampère and time. I think a unit of elementary charge is usually defined positive in Coulomb whereas an electron carries the charge $-1e$. It's a matter of taste and how much is the author willing to confuse his readers.
In particle physics you have the charge of an electron as elementary charge $-1$, in electrodynamics its $C>0$.

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