Natural Science Forum / Physics / Electromagnetism / November 2006

Can anyone explain the following:
Place an apple in a microwave oven
and after about 30 seconds
the apple expells steam from the center.

I understand that moving Halbach arrays over a conductive loop will
generate a current in the loop, which will in turn create an opposing
magnetic field.The only requirement for levitation is that the vehicle
must already be moving at a few kilometers per hour (roughly the same

Is the Biot-Savart's law, which is
           mu * i * (dl x r)
dB =  _________________________        (dB, dl and r are vectors)
                4*pi * r ^ 3

some time ago, I read about the use of magnetic fields to direct and
speed up particles in particle accelerators. From the article I read it
seems that the fields are specifically shaped to optimize the
accelerator. What I would like to know is what are the different ways

I have a question concerning Maxwell's equations.
In differential form, we have:
rot e = - @b/@t
rot h = j + @d/@t

Greetings everyone,
I have questions regarding the wave equation with respect to conducting
radiators... I would like to express the current J in terms of the wave
equation.