Recent content by ellocomateo

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    Graduate Component of the quadrupole Q_ij

    We are looking on the same graph, but I still do not see how I should label the axes. There is no information whatsoever on this point. Or at least I do not see it.
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    Graduate Component of the quadrupole Q_ij

    Thank you for commenting, but how does this translate to the i and j ?
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    Graduate Component of the quadrupole Q_ij

    Hello, I do not manage to visualize the link between the component of the quadrupole Q_ij and the spatial distribution of the electric quadrupole field. I was told to imagine the Q_ij as an ellipsoid, which I understand (the ellipsoid "radius" in a given direction being the strength of the...
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    Graduate Electric field boundary equation implication at air/earth interface

    Hello, I want to derive the electric field vector from a quadrupole potential. I am starting from faculty.physics.tamu.edu/pope/em603.pdf (6.32) and I am considering E=-∇\phi with \phi=1/2 Qijxixj/r5 I am very unsure if I carry out the thing properly, I would appreciate your comments...
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    Graduate Index Notation: ∂_i 1/r = -x_i/r^3?

    Oh, you mean chain rule and ∂r/∂i=xi/r Thanks!
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    Graduate Index Notation: ∂_i 1/r = -x_i/r^3?

    Hello world, Index notation is driving me crazy: why on Earth is ∂_i 1/r = -x_i/r^3 ? I would expect it to be -x_i/r^2... Thanks for commenting