[MLB-WIRELESS] Whats Faster ??

[Tony Langdon, VK3JED]

At 09:07 PM 12/08/2003 +1000, Stuart Anderson wrote:

>Wouldn't the distance from point A to point B have something to do with it?

Well, to settle the question, wireless is fastest in terms of propagation 
speed, because the signal travels at (only a tiny fraction less than) the 
speed of light in air.

Cables all have a "velocity factor" less than 1, and fibre consists of 
glass, which has a refractive index somewhat greater than 1 (making the 
velocity factor < 1).

Couple of notes:

1.  Air has a refractive index slightly greater than 1 (but not by much), 
so the propagation of radio waves in air is very slightly less than that of 
light.

2.  Velocity factor is the ratio between the speed of propagation along the 
cable and the speed of light (so actual velocity = velocity factor * 
velocity of light).

73 de Tony, VK3JED
http://vkradio.com 


To unsubscribe: send mail to majordomo at wireless.org.au
with "unsubscribe melbwireless" in the body of the message