Hi,

Could someone please provide a correct near field equation that a
computer programmer can understand? I'm using the following equation
in a simple simulation but it's not working in all cases.

E = a * sin(theta) * q / ( 4 * pi * e * c^2 * r )

The computer program uses the above equation to create tiny segments
of oscillating charge. The program simulates a wire carrying current
and a ferrite material. The way I am simulating the ferrite material
is by placing small loop currents.

According to the above equation, the near field from an infinitely
long wire should not change with distance. That is, the near field at
1 inch should be the same as 10 inches. This also agrees with the
near field results of an antenna-designing program. Now if that's
true, then how can an infinitely long wire generate a net voltage
across a closed circuit? If the electric field is uniform then the
net induced voltage around a closed circuit that is near the
infinitely long wire should be zero. But experimental results show
that to be completely false. OK, I couldn't find an infinitely long
wire, but a pretty long one. I entered the exact dimensions of my
experiment and the simulation results were completely off from the
experimental results. In fact, there was significant induced voltage
from a very long wire.

Can any one please shed some light on my error? BTW, the simulation
successfully predicted several other experiments when the theta angle
was zero. Obviously the theta angle goes from zero to 180 degrees in
an infinitely long wire. Am I using the wrong equation?

Any help is greatly appreciated,
CJ