# Divergence Meaning

1. Feb 19, 2009

### salman213

1. I was just trying to understand what divergence means so I hope someone can help me out.

Well from what I have read if I take a vector field and use an infinitesimal region, if the vector going in is smaller than the vector going out there is positive divergence.

Does this mean if i make a circle with UNIT VECTORS there is ZERO divergence. Because what is going in, is the same as going out,

[URL][PLAIN]http://img11.imageshack.us/img11/9028/31455816et8.jpg [Broken]

If they were NOT unit vectors or vector of the same magnitude then there Would be divergence? is that the correct concept?

2. Relevant equations

3. The attempt at a solution

Last edited by a moderator: May 4, 2017
2. Feb 19, 2009

### tiny-tim

Hi salman213!

If you mean unit vectors all going out from a particular point, and a small circle round that point, then there is divergence, because all the vectors are going out of the circle.

Zero divergence means conservation of whatever-it-is …

often you have zero divergence everywhere except at "sources" and "sinks" …

eg an electric field with zero divergence except at the "singularities" where point charges are.