There is only one field electromagnetic field.

It has two components, electric and magnetic.

One component cannot exist without the other.

As the field travels through space at the velocity of light, one component
generates the other, and vice-versa.


The magnetic field, as it sweeps by at high speed, induces a current in a
short wire bent into the form of a loop.


The electric field, as it sweeps by, induces a voltage between the ends of a
short straight length of wire (a dipole).


On a long length of wire of any shape, an appreciable fraction of a
wavelength or longer, both appreciable currents and voltages will exist.


To sum up, a small loop is most sensitive to the magnetic component as in an
electricity generator, and a straight wire with its ends is most sensitive
to the electric component. But both effects MUST act together. They cannot
be considered in isolation. As in any other electrical circuit Amps and
Volts are always related by a resistance which depends on the length and
shape of the wire.

And there are many more ways of describing it.
---
Reg.

Hello group,

This is ONLY true for 'far field' sources.
In the Far Field ( 1 wavelenght) according to maxwell's law
the E-field and H-field are mutual dependent.
(natural impedance is : 120*Pi=377 Ohm)
In the Near Field ( 1 wavelenght) this is NOT true.
The natural impedance drops for H-field and raises for E-field.
This is why loop antenna's are less sensitive for local interference,
like light dimmers, TV sets ect.

Maarten Hagg
the Netherlands


"Reg Edwards" wrote in message
...
There is only one field electromagnetic field.

It has two components, electric and magnetic.

One component cannot exist without the other.

As the field travels through space at the velocity of light, one component
generates the other, and vice-versa.


The magnetic field, as it sweeps by at high speed, induces a current in a
short wire bent into the form of a loop.


The electric field, as it sweeps by, induces a voltage between the ends of
a
short straight length of wire (a dipole).


On a long length of wire of any shape, an appreciable fraction of a
wavelength or longer, both appreciable currents and voltages will exist.


To sum up, a small loop is most sensitive to the magnetic component as in
an
electricity generator, and a straight wire with its ends is most sensitive
to the electric component. But both effects MUST act together. They
cannot
be considered in isolation. As in any other electrical circuit Amps and
Volts are always related by a resistance which depends on the length and
shape of the wire.

And there are many more ways of describing it.
---
Reg.