# Re: Need help comprehending EM

```In a message dated 96-07-17 09:36:11 EDT, you write:

> I am stuck with a picture I
>  keep seeing of the x, y and z axis picture where there z axis is
>  time, y axis is the electric wave (a sine wive in the picture) and
>  the x axis is the magnetic wave (also a sine wave). My problem is
>  that I can not picture this in my mind in reality.

Hi Bob,

Try re-orientation of the graph ==>

Let the x axis be the time (wavelength ) vector
Let the y axis be the electro-static vector
Let the z axis be the electro-magnetic vector

sine waves over cities don' do much to give one a
feel for three dimensions -- :-)

consider a point source transmission ------360 degree radiation ----(in
all planes).
Then the energy radiated could be considered to be an expanding  sphere
within an expanding sphere......the distance between each sphere being 1/2
wavelength
of the frequency of the transmission with the radius of each representing the
points
of maximum ES & EM .
Draw a circle ---- then a radius (drawn as a sine wave ). Then draw
smaller
circles within the origional circle--- with their respective radii at the
peaks of the sine wave (ES-EM-- max)

Consider the ES vector a super-sonic aircraft ---- When the craft goes
sub-sonic -- the "sounds " (EM) ---leave it & continue on to break windows
:-)

---- I dunno ---- As far as Maxwell is concerned --- i need a DUH fer dummies
:-)

Hope this helps

Sandy
```