In a microscopic view, electrons only drift by a small distance when conducting So if a wire is transferring 100Mbps, the electrons contributed to this transmission is next to the load, and only electromagnetic waves (Electric field) travel at speed of light? Am I correct? Thanks Jack
Pretty much correct. I like to give this example: Consider the electrons to be marbles, and the wire to be a pipe whose diameter is a bit bigger than one marble. The pipe is thus full of marbles in single-file, but all touching. If you push on the marble at one end of the pipe, the marble at the other end moves out "immediately", at the same slow speed you pushed in the first marble. In reality, there was a delay (speed of sound in marbles?) for the pressure pulse to propagate alnong the chain of marbles in the pipe, but this is negligible to the eye.
The same thing happens with electrons in a wire, where the propagation is at (about) the speed of light even though the individual electrons are much slower. It's the propagation (of information or energy) that we are normally interested in, not where any given electron is. But note that *all* the electrons (like the marbles in the pipe) are "contributing" to the transmission, each passing it along to its neighbor. It's just that we only have contact with the ones on the ends.
Hope this helps!
Bob Masta dqatechATdaqartaDOTcom D A Q A R T A Data AcQuisition And Real-Time Analysis
I quite like that, nice summary :)
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.