Electric flux (16-6)
Question 1 of 5
Question
Magnitude of the electric field due to a point charge Q
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Review
Figure 16-17 shows how we extend the idea of flux to the electric field. Instead of a pipe carrying a fluid, let’s look at a region of space where there is an electric field →E. We saw in Section 16-5 that the value of →E can vary from point to point, so we consider a small enough region that we can treat →E as having essentially the same value over that region. We then imagine a small rectangular area A that we can orient however we like. By analogy to the flux of water in Figure 16-16, we define the electric flux \boldsymbol{\Phi} (the upper-case Greek letter phi) through the area A as follows:
