Line of infinite charge and a gaussian sphere

AI Thread Summary
To analyze the electric field around an infinite line of charge using a spherical Gaussian surface, one must recognize that the symmetry simplifies the calculations. The flux through the ends of the sphere is zero, while the flux through the curved surface can be determined by integrating the electric field E(r) over the sphere. This integration, although potentially tedious, demonstrates the effectiveness of Gauss' Law in leveraging symmetry. By calculating E(r) at a polar angle θ and integrating, the relationship can be established to show that the total flux satisfies Gauss' Law. Ultimately, this exercise highlights the utility of symmetry in electrostatics.
stunner5000pt
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Construct a spherical gaussian surface centered on an infinite line of charge. Calculate the flux through the sphere and thereby show that it satisfies gauss law.

I know how i can do it for a cylinder, but a sphere?

I know that the ends of the wire (one diameter) wil have zero flux at it's ends

but wouldn't i have to integrate over a big hemispherical surface and then multiply by two but ... wouldn't it be tedious?
 
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stunner5000pt said:
but wouldn't i have to integrate over a big hemispherical surface and then multiply by two but ... wouldn't it be tedious?

Yes, but that's probably the reason they're asking you to do it. It shows the power of symmetry in applying Gauss' Law.
 
It's not hard. You know what E(r) is. Take a point at polar angle \theta and find E(r).n in terms of \theta. Integrate over the sphere.
 
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