Recent content by Crusoe

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    Resistance to change in temperature?

    All substances have a "specific heat capacity", which is a measure of the material's capacity to store heat. This is sometimes described as "thermal mass", a useful but not entirely accurate analogy. For example, water has a higher specific heat capacity than air...
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    Electric current density in conductors not resembling a wire

    Ah, thanks. I did electrostatics in college physics many years ago. A click just went off in my head, now I see the relevance to electrostatics. You just substituted the permittivity of free space for separated charges, with that of the metal plate.
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    What is the explanation for magnetic pinching in plasmas and conductive fluids?

    Can someone give me an intuitive explanation why plasmas or conductive fluids tend to follow magnetic flux lines? E.g. http://en.wikipedia.org/wiki/Magnetohydrodynamics" entry on this says: If I take a stab at a qualitative explanation, is it because magnetic flux lines are equipotential...
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    Electric current density in conductors not resembling a wire

    Yes it does, thanks for the clear response! :) Is an intuitive interpretation of \nabla^2\phi=0 in the context of electrical voltage, that the net or sum change in voltage equals zero? IOW the vector calculus form of Kirchoff's Second Law for circuits. Can you recommend a good online...
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    Electric current density in conductors not resembling a wire

    Let's say you have a square plate with a voltage applied across two opposite corners, connected by the hypotenuse. Presumably, the electric current density distribution throughout the plate would be such that it would follow the path of minimal resistance, i.e. through the hypotenuse. If...
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    Some questions on properties of superconductors

    Hi all, I was wondering if someone can explain to me whether: 1) Superconductors are attracted to originally unmagnetised ferromagnetic or paramagnetic materials? AIUI superconductors are perfect diamagnets due to the Meisnner Effect, and magnetic attraction is due to the creation of...
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