Recent content by rockbreaker

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    What Determines the Electric Field Inside a Spherical Cavity?

    You're right, I actually confused this problem with a dielectrical sphere. It is pretty obvious using Gauss' Law that there has to be an electric field inside the cavity when there is a charge inside it (which ends at the surface of the cavity to guarantee that the conductor is field-free)...
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    Surface charge density on a cylindrical cavity

    That's a great idea, thank you very much. I first tried to solve this problem with image charges, but the problem is that I don't know where to place it. In the solution of Laplace's equation, all coeficients for any term r^n for n<0 must be zero, but can there survive any others than the...
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    Electric Field Inside an Electret Cylinder?

    b) As there are no other charges involved, I think the field inside the electret is σB=P*n=-P E=σ/ε0=σb/ε0=-P/ε0 For c), I would like to use the expansion of the potential, V=1/4∏ε0*(Q/r+r*p/r^2), where the dipole term dominates because we are far away from the electret. But isn't r*p=0...
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    Electric Field Inside an Electret Cylinder?

    Homework Statement I would like to refer to this problem about the electric field inside an electret. https://www.physicsforums.com/showthread.php?t=444106 An elecret is a dielectric that has a quasi-permanent polarization when there is no applied field. Consider a uniformly polarized...
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    What Determines the Electric Field Inside a Spherical Cavity?

    Hi, I am dealing with a problem in Electrostatics. Homework Statement There is a sphere with a spherical cavity in it. The sphere itself does not have net charge, but inside the cavity, there is a point charge at the center of the cavity. What's the electric field inside the cavity? Homework...
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    Surface charge density on a cylindrical cavity

    Hi folks, I am having trouble generalizing a well-known problem. Let's say we have a cylindrical cavity inside a conductor, and in this cavity runs a line charge λ. I would now like to know the surface charge density on the inside wall of the cavity, but with the line charge not in the center of...
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