how Internet back in the copper wire days could still transmit data in seconds when Electrons flow through copper at a few metres per second.
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The premise is wrong, electricity still flows at insanely fast rates. It entirely depends on the setup, but it can go from 1/2 of c to 99% of c. At worst, it’s a couple hundred million meters per second.
>electrons flow through copper at a few metres per second.
If this were true, You would be fine standing 10 meters away from me holding a live wire provided you let go the second you see me flip on the switch. I don’t need to tell you that that is not happening. Also, you’re foregoing the fact that copper wires only account for part of the network, the backbone still runs on fiber.
>how Internet back in the copper wire days could still transmit data
We’re not past using copper wires, only wealthy countries can really afford to route fiber cables all the way to customers’ homes, and it’s still prohibitively expensive for many households.
Imagine a jump rope. Two people each holds one end. The two agree to communicate by swinging the rope up and down causing a “wave” to flow from one end to another. None of the molecules in jump rope move from one end to another and yet the wave still moves.
This is electricity. Electrons don’t need to “flow” for an electrical circuit to send a signal. The energy of the signal is contained in waves. The speed of that wave is the speed of light.
The speed of electron drift is a few meters per second yes, but transmission of power and data is more analogous to the speed of sound, than it is wind. Wind speed is the speed of the air to moving from point A to B. Sound like a blast wave from an explosion travels as a pressure wave, much much faster.
With electrons the electrons all push away from each other much like gas molecules in air. Power and signal data travels much much faster than a few m/s and is generally above 50% light speed.
Old superlong cables in the days of telegraphs -did- have issues with data rate because of signal propagation issues. High capacitance wires, leakage into the environment, low drive power, no inline repeaters, etc. But those issues had been mostly solved by the time we had actual telephones.
Imagine you have a line of cups with ping pong balls in them. The cups represent atoms in the wire, and the ping pong balls represent the electrons. Imagine each cup can only hold one ping pong ball, and you add a ping pong ball to the cup on the left. The ping pong ball that was already there shuffles to the cup to the right. But that cup also can only hold one ping pong ball, so the ball that was already there shuffles to the right. And so on.
This is how electricity is working — each “ping pong ball” moves comparatively slowly, but the way they force each other down the line is significantly swifter. When we talk about signals in this way, we don’t much care about the speed of a single electron; we care about the speed of the whole system.
Electrons moving are not the cause of energy flow, they are an effect.
The energy is carried using fields that actually work outside of wires.
We are not using the electrons to transmit the data. We actually use energy to do that.
This is in fact very deep topic, please refer to these videos if you are interested in exploring it:
[https://www.youtube.com/watch?v=C7tQJ42nGno](https://www.youtube.com/watch?v=C7tQJ42nGno)
And this:
[https://www.youtube.com/watch?v=oI_X2cMHNe0](https://www.youtube.com/watch?v=oI_X2cMHNe0)
Pulses of electricity convey signals along a wire. But electricity is not electrons travelling down the wire. Very roughly, electricity is the impulse of energy that electrons convey by bumping into their neighbors.
In this way, electricity is like sound. You can hear an explosion from a mile a way about 5 seconds after detonation. The air itself didn’t travel one mile; the impulse that air molecules convey to each other travelled one mile.
Picture two people holding a meter long ruler. One pushes on one end just a little bit and the other feels it. No atom in the ruler has moved more than a few centimeters, but the *information* has traveled all the way to the other person.
It’s not the actual electron that needs to move but the energy it’s carrying. It’s basically like a newton’s cradle toy with the metal balls on strings, even though most of the balls aren’t moving they can still transfer movement/energy from one ball to another.
There’s a strong wind on a field with a bunch of soccer balls. The balls roll down the field slowly due to the wind pushing and the balls hitting various things, so the wind is much faster than the moving balls. That’s basically analogous to electricity on a wire. An electric field moves the electrons down the line. The electrons hit stuff and move slowly. The electric field moves quickly. It’s all about the field propagating, not the electrons.
Electrical signals can actually transmit though copper wire faster than signals through optical fiber.
In both cases the speed of the signals is measure as a percentage of the speed of light. (optical cables are about 2/3 the speed of light while copper wire can be anything from half of it to 90% of it depending on the cable)
So it is not a big difference.
It does not actually take an electron to travel all the way for the signal to travel.
To see how this would obviously be the case imagine sound.
If you say something that signal is transmitted tot he ear of the person hearing it at the speed of sound. however the air between you and the person listening is not actually moving at such high speeds. You don’t create ultra hurricane level winds when talking.
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