By Faraday definition there two methods of electrisity generationutilizing magnetic field: a) the magnetic flux must changed througn a wire ring; b) a wire must cross the magnetic flux
May be there is also a third generation: the magnetic disc, that involves not only magnetism and electricity , but also the inertial properties of space and time....
If the Maxwell equations are valid (and they seem to be valid within certain limits) the two effects must produce the sam result ...
Wow this is interesting question ! I agree with Gyorgy ...but what IF :)
I agree with Mr. Banhegyi.
It is absolutely impossible in vacuum. It may be easily obtained from the second Maxwell;s equation . More complicated cases of nonlinear and/or anisotropic mediums as well as the case of high velocities need to be verified more carefully.
Hello Gyorgy,
I would be most interested to know the "limits" within which the 4 equations are valid.
Which equation becomes in valid?
The speed of light is related to the permittivity and permeability of free space if Maxwells equations are invalid then the relation square root of (eps0 x mu0) will not hold as these equations may be used to derive that relation - what happens to the pointing vector - does radiation cease?
Jeremy
I only meant the limitations of classical physics in general - with respect both to relativity theory and quantum mechanics. Maybe I should have told it.
My 2 cents worth:
In an EM wave in free space an electric field exists without the presence of charge carriers - J.C Maxwell introduced the concept of Displacement current. Energy is exchanged between the electric and magnetic fields and power flows orthogonal to the E and H vectors ie. P= E X H (read this as E cross H)
Gyorgy- speaking of relativity, I believe it may be useful to recall that when Maxwell's equations are formulated appropriately for relativity, it is easy to see that (a) the magnetic flux must changed througn a wire ring; and (b) a wire must cross the magnetic flux; are interchangeable--given an appropriate change in the observer's inertial reference frame. "One man's magnetic field is another man's electric field." I hope this helps. But then to answer your question, I believe that in a single reference frame, the effects are indistinguishable. If both phenomena are present, the fields resulting from each of them are additive, due to the linearity of the vector relations in Maxwell's equations. You would need to perform control measurements (a without b, and b without a) to see how each phenomenon individually affects the fields.
first question:
in a rectangular coordinate system, suppose two frames (S and Sbar) in relative motion in x direction. x components of E and B fields are the same in both frames. But y and z components of Ebar and Bbar will be transformed:
Ebar_y = gamma*(E_y - v*B_z)
Bbar_y=gamma*(B_y+(v/c^2)*E_z)
Ebar_z=gamma*(E_z+v*B_y)
Bbar_z=gamma*(B_z-(v/c^2)*E_y)
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