4 ms·
And the "electric signal" is an electromagnetic wave- also known as light. Nowhere did they imply the speed of light in a vacuum, the speed of light in copper i
by SpaceRaccoon 6y ago
And the "electric signal" is an electromagnetic wave- also known as light. Nowhere did they imply the speed of light in a vacuum, the speed of light in copper is an equally valid interpretation.
- mhh__ 6y agoThat's true but it's easy to forget that the velocity factor of that wave is significantly smaller in (say) copper than air or a vacuum.
- SpaceRaccoon 6y agoThe velocity factor of light in glass is also significantly smaller, about 70%.
- adwn 6y ago> And the "electric signal" is an electromagnetic wave- also known as light. No, it's not. If it were, you'd have photons moving through your copper wire, which would be quite the sensation! A moving electron does create a change in the electromagnetic field, however, so maybe that's where your confusion stems from?
- ben_w 6y agoMore charitably, charge carriers do move much more slowly than the electric field they transmit[0], and while you’re correct that the time-varying electric field in a processor is not light (nor even a radio wave), if the chips were much larger or much higher frequency the chips and buses would risk becoming antennas and having all the problems that would bring — 5 Ghz ~= 6cm wavelength [1] ~= 3cm half-wave dipole. [0] https://en.m.wikipedia.org/wiki/Speed_of_electricity https://en.m.wikipedia.org/wiki/Speed_of_electricity [1] http://www.wolframalpha.com/input/?i=c%2F5ghz http://www.wolframalpha.com/input/?i=c%2F5ghz Edit: if the chips were much larger. Smaller chips can go faster without becoming antennae.