Tangential components of the electric field across an interface between two media, with no impressed magnetic current densities along the boundary of the interface, are continuous. So: $ n \times (E_2 - E_1) = 0$. Now suppose an lumpedenter image description here circuit with some elements that are connected with infinite electric conductivity wire $(\sigma = \nsim)$ $\longrightarrow E_1t =E_2t = 0$ (in the wire and cylinder). What makes electrons move along the cylinder when there are no tangential components of the electric field?

lumped circuits : http://en.wikipedia.org/wiki/Lumped_element_model

  • $\begingroup$ could you link to an image of what sort of circuit this is? $\endgroup$ – anna v Mar 8 '14 at 13:53
  • $\begingroup$ @annav: better ? $\endgroup$ – rza Mar 8 '14 at 20:53

To set the record straigth, conductivity cannot be infinite, an ultimate limit will be given by the velocity of light which can never be over shot. It can be very large as in superconductors but even there, it is limited.

You are talking of conductors at electrostatic equilibrium., static electricity. For your vector conclusions to be true there should be no current in the surface. While the charge is being built up there exists a current in the circuit.

When there exists current in the circuit the surfaces cannot be charged as the electrons move so as to neutralize the charge imposed by the power source. Have a look at the answer here today to a similar question.

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