Take the 2-minute tour ×
Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free.

A negatively charged molecule will generate a field, an electric field, and it will repel all negative ions.

So what does positively charged molecule generates that causes other positive molecules to be repelled?

share|improve this question

1 Answer 1

It's still called the electric field. It just now has a positive sign instead of a negative sign.

share|improve this answer
so there are 2 types of electric fields one is positive and one is negative. –  Muhammad Umer Dec 30 '13 at 1:04
Yes, you can think of it that way. But more generally, it is called simply "the electric field" and its sign, magnitude, and relation to position all depend on the source charges and where the charges are. For more details, look at hyperphysics.phy-astr.gsu.edu/hbase/electric/elefie.html. The sign of $Q_source$ is what changes the sign of the electric field. –  mcFreid Dec 30 '13 at 1:09
i've heard that magnetic field and electric field co-exist. So what is the sign of those electric field, source being normal everyday magnet. –  Muhammad Umer Dec 30 '13 at 1:13
They co-exist in the sense that both fields depend on the charge of the particle and they also depend on each other. Google "Maxwell's equations" for details. Electromagnetism is a huge subject and can't be taught via the comment section. As for normal everyday magnets, to understand those is also a rather large subject (Google "Ferromagnetism"). Lastly, everyday magnets don't generate an electric field (they have no net charge) unless you run a current of electrons through them. –  mcFreid Dec 30 '13 at 1:22

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.