Figure22.7.1.Two points and an imaginary square loop.
The figure above shows an imaginary square loop centered between two points \(A\) and \(B\text{.}\)
(a)
Choose an area vector for the loop.
(b)
Suppose a point charge \(+Q_o\) is located at point \(A\text{.}\) Is the electric flux through the loop positive, negative, or zero?
(c)
Suppose a point charge \(+Q_o\) is located at point \(A\) and a point charge \(+2Q_o\) is located at point \(B\text{.}\) Is the electric flux through the loop positive, negative, or zero?
(d)
Suppose a point charge \(+Q_o\) is located at point \(A\) and a point charge \(-2Q_o\) is located at point \(B\text{.}\) Is the electric flux through the loop positive, negative, or zero?
Explanation22.7.2.Flux.
Figure22.7.2.Two point charges and a Gaussian cube.
Two positive point charges \(+q\) are located a distance \(L\) apart, as shown above. A Gaussian surface (a cube with side length \(L\)) is drawn with its center at the location of the left charge.
(a)
Is the electric flux through the right face of the cube positive, negative, or zero?
(b)
Suppose the charge on the right were replaced by a charge of \(-q\text{.}\) Would the net electric flux through the entire cube increase, decrease, or stay the same?
SubsectionMetacognitive Reflection
A major theme of this unit was determining how and when symmetry can help make your calculations easier. Write a short paragraph summarizing symmetry and how it can be useful when calculating the electric field. Which activities did you complete this week that you want to remember?
