Let's take Coulomb's Law as an example. In SI units:
where
In electrostatic or Gaussian units, however, it has a simpler form:
The unit of electric charge here is:
To establish the relation between (1.1a) and (1.1b), we should rewrite them as:
Let's assume , which means both
and
hold in (1.1a') and (1.1b'). By dividing them we get
or
Now we have a question: How many statC does a coulomb equal (correspond) to?
Let's apply (1.3) as:
Then we have: [1]
Here we use (1.2) and the conversions and
.
We represent (1.4) as: [2,3]
- Here is the calculation.
- This is for electric charge only. For electric displacement flux, (1.3) does not work.
- Before 2019,
exactly.