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Homework Help: Conduction and displacement current density

  1. Jun 17, 2005 #1
    Could anyone help me solve the following problem?

    Calculate the ratio of the conduction current density to the displacement current density of the electric field [itex]E = E_0 \cos(\omega t)[/itex] in copper, to a frequence of [itex]f = 1 kHz[/itex]. (Given: [itex]\epsilon_{Cu} = \epsilon_0[/itex], [itex]\rho_{Cu} = 2 \times 10^{-8} \Omega m[/itex]).​

    First, I calculated the displacement current density:

    [tex]J_d = \epsilon_{Cu} \frac {dE} {dt} = - \epsilon_0 E_0 \sin(\omega t)\omega[/tex]

    I'm not sure if it's correct. Besides, I don't know how to find the conduction current density. I thought about using:

    [tex]\vec{\nabla} \times \vec{B} = \mu_0 (\vec{J} + \epsilon_0 \vec{J_d})[/tex]

    But is there a magnetic field? I'm confused...
    Last edited: Jun 17, 2005
  2. jcsd
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