What is the "speed" of electricity?

Question

OK, I know the speed of light in vacuum, and the speed sound in a given medium. But if I had (say) 1km of wire, a BIG battery, light bulb and a switch connected in series (or slightly more technical version thereof). How long after closing the switch would it take for the bulb to light? Doubtless it depends on the voltage?? But say with these old transatlantic cables there must be some measureable delay?? Just wondered? any thoughts?

Answer 1

Actually the individual electrons flowing in the circuit move at slow speeds. Imagin a pipe one foot in diameter full of marbels. If you push one marble into the pipe one marble pops out of the other end. If the marbels are stacked nicely say there are 100 marbles across each marbel had to move 1/100 marble diameters to get one to pop out the other end. electron flow is like that only there are a very great number of conduction sites across the diameter of even a small wire. there is a good discription of the whole thing here-
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/ohmmic.html

Answer 2

There are two things to consider.
1. The actual drift of the electrons. Say for an electron to flow out of a battery and into the filament of a light is slow.
2. the voltage, signal is very fast. The voltage travels down the wire to the light very fast so the light comes on very fast. This can vary with material. Integrated circuits are starting to use copper since it will speed of the circuits. (It likes to diffuse into the transistors destroying them so barriers are needed)
Might think of this as the electrons bump into each other and the next one until there is flow at the filament,(or something) so the time between switching and seeing something come "on" is very fast.

Answer 3

Ah some one who doesn't know his esoteric theories I see.
electricity is presumed to be a flow of electrons through a circuit.
however this 'flow' shows wave and particle properties. The driving force is the potential difference between the power source and the light bulb. Although the electrons are presumed to be passed from atom to atom along the copper wire. However because of the fact that this 'exchange' is presumed to flow along the circuit but the pd remains constant then we move into the realms of quantum physics where all these transfers take place at the same time. So it is generally presumed to be at the speed of light but may in fact be instantaneous. Cant go any deeper than that I only went to elementary school. lol

Answer 4

electrical energy would properly be powered by utilising any source of gasoline so it is going to be the main achievable. you are able to charge it in any way, subsequently, considering we don't understand what source we would choose to apply for subsequent gen automobiles, we would to boot use electrical energy because of the undeniable fact that's powered by utilising something!!! Make a hydrogen gasoline cellular potential plant, or a bio diesel plant, or another cool new form of potential plant that no person even is conscious approximately yet, and potential your electric powered motor vehicle from that! electrical energy is freakin amazing like that. until eventually we stumble on a achievable "green" potential source electrical energy make a large selection because of the fact the refueling device is already set up (in the journey that your place has lively electric powered retailers that's a potential refueling station), subsequently there isn't any would desire to create an completely new refueling infrastructure. to not point out that's lots extra low-fee.

Answer 5

The speed of electricity is essentially that of light. The simplest analogy I can give you is the one I was taught about a hundred years ago. Any conductor of electricity has many free electrons waiting to be dislodged from its atoms. They exist along the entire length of the conductor. Now think of a wire, any conductor of electricity as being analogous to a hollow tube filled with ping pong balls from one end to the other, and think of the ping pong balls as electrons.

The tube, like the wire is filled. If you push another ping pong ball into the tube at one end, a ping pong ball is instantaneously expelled from the other end of the tube. Similarly, when an electrical pressure (voltage) is applied to a conductor in a closed circuit, the first electron from the voltage source entering the wire, causes an electron to instantaneously exit the wire at the opposite end of the circuit.

As far as delay due to distance is concerned, it can be calculated by the speed of light (186,000mi/sec) divided into the length of the circuit (wire, cable).

Answer 6

You will get a voltage drop, loss of power (watts) over a long distance.
What I was told a battery may have a delay if in low temperature, yet we are talking 1/1000 of a second.

I'm not a hundred percent sure on AC current, as that would work on hertz, if you drop the hertz rate some thing might change.

Hope that helps.

Answer 7

Apart from voltage it also depends on the material of the cable as well as the insulation. It also differs wether you use ac or dc. All these things depend on the use. The actual speed varies from few meters per second upwards.

Answer 8

Generally speaking electricity is travelling at speed of light.

When the electricity is in a different medium, then the speed is different.
For example, on a FR4 PCB, the electricity travel at 6 inch every nano seconds. That means it travel 500 million feet per second.

Answer 9

not sure but the variables are irrelevant I think electricity travels at the speed of light regardless of resistance,temperature,voltage etc. It's a bit like gravity's affect on an object its a constant regardless of weight,mass,size,shape etc

Answer 10

It's the same as the speed of light, 186,282.397 miles per second.or 299,792,458 meters per second.

It's "speed" is the same regardless of cable length, battery size, voltage etc.

It's a physical constant.