At 2:28 PM +0100 9/15/97, Adrian Bool wrote:
On Mon 15 Sep, Susan R. Harris wrote:
Photons propagate at 0.65c in fibre - the exact speed does vary depending on whether its single or multimode fibre.
Hi Geoff - not to reveal my ignorance or anything, but ... is that 65 degrees celcius?
65% the speed of light in a vacuum ?
The equivalent EMR propagation speed in coppr is 0.75c
What is EMR?
Electo-Magnetic Radiation. Electrons don't count as EMR do they though, (hell they have a mass!) so data in the form we transmit it down copper won't move at this speed will it?
True, electrons have mass, but we are not 'transmitting' electrons. We are oscilating the electrons in the media. This oscilation creats EM energy which propogates down the media, in the form of photos, and will propogate at some percentage of c depending upon the media. Greg =================================================================== Greg Shepherd Springfield Public Schools Systems Engineer (541) 726-3268 gshepher@sps.lane.edu "...It is somewhat of a rude awakening for many of these parents to find that America is facing a most serious situation regarding its popular music. Welfare workers tell us that never in the history of our land have there been such immoral conditions among our young people, and in the surveys made by many organizations regarding these conditions, the blame is laid on jazz music and its evil influence on the young people of today... That it has a demoralizing effect upon the human brain has been demonstrated by many scientists." - Ladies Home Journal, 1921 ===================================================================