Re: [Phys-l] g & E fields

[carmelo@pacific.net.sg]

Quoting Jeffrey Schnick <JSchnick@Anselm.Edu>:
> It seems to me that the question about where the energy is located is a
> scientific question.  Energy of a system calculated in the center of
> mass reference frame of the system is mass of the system.  In principle,
> all you have to do is carefully map out the gravitational field of a
> charged capacitor to determine the distribution of mass, and hence
> energy in the center of mass frame, in the capacitor.  Another option
> would be to measure the moment of inertia of the charged capacitor.

How do electric or magnetic field store energy should also be a  
scientific question. However, we should be honest to our students that  
there is still no satisfactory answer to this question yet. Neither  
can Bernard's question on measurement be easily answered too.

Here is another tricky question on the energy of the electromagnetic  
wave: Is the intensity of the bright fringe (For example, Young's  
Double Slit Experiment) always the same when the electromagnetic field  
is varying? Neither is this question easy to be explained too.


Alphonsus