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Coulomb's epsilon zero and its name

  1. Aug 30, 2005 #1
    In Coulomb's law the term epsilon zero appears in the denominator and receives the name of permittivity constant [\b]. As it comes from the word permit (allow) then it would seem reasonable, for me at least, to expect that, as epsilon zero increases, the vacuum would be allowing one charge to better "see" the other, and then the force would be greater. But it is the opposite.

    Is this name justifiable in some acceptation of this word ?
  2. jcsd
  3. Aug 30, 2005 #2
    Epsilon zero is the ratio between the charge enclosed by a surface and the electric flux through that surface. The name "permitivity of vacuum" is archaic and pointless.
  4. Aug 30, 2005 #3
    But consider a space full of smoke. If the force had to do with seeing the other, this part played by the space has some sense in permiting the force to cross the space in between.

    I would like seeing epsilon zero in the numerator so as to call it permitivity.
  5. Aug 31, 2005 #4


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    Homework Helper

    A large value of epsilon "permits" lots of charge
    to build up, with fairly small Voltage.

    It's archaic, and inverse to the physicists' viepoint
    which usually emphasizes the fields,
    but is reasonable for engineering purposes (as in capacitors).
  6. Sep 2, 2005 #5
    I am satisfied with this answer. The capacitor view point is quite understandable.

    Best Regards,

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