# Electric flux (positive, negative, or zero?)

1. Sep 12, 2009

### rwrem

1. The problem statement, all variables and given/known data

Imagine a positive point charge on the left side of the picture and an area defined by a loop on the right. I was asked to draw and label the area vector and sketch the electric field lines due to the point charge, which I did. The next questions asks:

Is the electric flux through the loop due to the charge positive, negative, or zero?

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My inclination is to say positive because the direction the area vector points is the same as the direction of the electric field lines.

But, the materials I've seen so far talks about the the electric flux flowing into or out of some enclosed box or sphere and never really mentions that an electric flux can be positive or negative. I can understand where you could get a zero total flux answer, where the flux flowing into and out of a box is the same, but am not sure how that relates to the situation above.

Again, due to missing some classes due to swine flu, I may have missed some fundamental explanations...

2. Sep 13, 2009

### rwrem

So, I guess it's positive, then? Seems logical to me, but I'm surprised no one has commented yet...