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Cyrus
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Gauss's Law HELP!
I need some help with Gauss's Law. In the book it states that if you have an irregular shape, then you can project each piece of that irregular shape onto a sphere. And since a sphere has field lines everywhere perpendicular to it, it makes life very simple because the flux will be the charge divided by epislon q/e. My question is this: do we draw infinitly many circles and project them for each dA, or is there one single sphere of radius r that we use when we project each little dA onto it.
If the latter is the case, then do we have an implication that the sphere we project it onto will have a radius r that is equal to the closest point on the irregualr bodies shape to the point charge within it? Because if we project onto a sphere of radius r, and there are points that lie lower than r, you could not project onto it could you. The closest point would have to be the maximum radius you could possibly use.
I attached a picture. You can see the irregular surface. Now I made a violet circle of radius r, who has a center that coincides with the point charge. Does gauss's law state that I can represent this charge having a flux through this irregular shape the same as if i calculated it through this one voilet circle?
(assuming I factor in projection scaling.) And if this is so, does that mean that the radius of my circle is restricted to the radius of the closest point from the center to the irregular body? Maybe this is a clearer explination of my question.
I need some help with Gauss's Law. In the book it states that if you have an irregular shape, then you can project each piece of that irregular shape onto a sphere. And since a sphere has field lines everywhere perpendicular to it, it makes life very simple because the flux will be the charge divided by epislon q/e. My question is this: do we draw infinitly many circles and project them for each dA, or is there one single sphere of radius r that we use when we project each little dA onto it.
If the latter is the case, then do we have an implication that the sphere we project it onto will have a radius r that is equal to the closest point on the irregualr bodies shape to the point charge within it? Because if we project onto a sphere of radius r, and there are points that lie lower than r, you could not project onto it could you. The closest point would have to be the maximum radius you could possibly use.
I attached a picture. You can see the irregular surface. Now I made a violet circle of radius r, who has a center that coincides with the point charge. Does gauss's law state that I can represent this charge having a flux through this irregular shape the same as if i calculated it through this one voilet circle?
(assuming I factor in projection scaling.) And if this is so, does that mean that the radius of my circle is restricted to the radius of the closest point from the center to the irregular body? Maybe this is a clearer explination of my question.
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