How can evidence from an experiment be explained in relationship to the hypothesis?

The purpose of the experiment is to TEST the hypothesis. 

If the results of the experiment seem to agree with the
hypotheses, then you're on your way ... there's a good
chance that the hypothesis is correct.

If the results of the experiment seem to NOT agree with
the hypothesis, then there's something wrong somewhere,
and you have more work to do.  You have to re-examine
the hypothesis, review the setup of the experiment, and
review the results, and also do some more experiments
if you have the time and can get the money.

Because it has a strength AND a direction.

Two separate charges that both cast their fields over the same place
can cancel each other out at that place if they're located just right.
You can't do that with scalars.