How fast does electricity travel?

Theoretically, the transmission speed of electricity is the same as the speed of light, which is about 300,000 kilometers per second; that is to say, it only takes about 0.03 seconds for electricity to travel 10,000 kilometers. What we call the speed of electricity is basically the speed at which electromagnetic waves propagate; and light is exactly a kind of electromagnetic wave.

The "speed of electricity" is about 300,000 kilometers per second. It only takes about 0.03 seconds for electricity to travel 10,000 kilometers.

Why can electricity run so fast?

1. First, let’s talk about how wires send electricity from several meters, hundreds of meters or even thousands of kilometers away:

The reason why wires and other conductors can conduct electricity is Because there are electrons in it, they are free and move randomly in the conductor before the circuit is connected. As soon as the circuit is connected, these electrons will begin to flow in an orderly manner as if they heard a command, forming an electric current. The average value of this orderly flow velocity of electrons is called the "electron drift velocity". This is not a racing driver's drift, this speed is not fast at all!

The drift speed of electrons in a conductor is related to factors such as the mass and length of the conductor. Generally speaking, it is very, very slow, often less than 1 mm/second. It's just slower than a snail! Calculating this way, how many centuries will it take for the electrons at the power plant to drift to my house...

The drift speed of electrons is so slow, of course it cannot be the "speed of electricity" that we usually call, which is approximately equal to the speed of light. .

2. In fact, there is another speed in the transmission of electricity:

After the circuit is connected, an electric field will be formed around the wire to promote the orderly flow of electrons, thus forming a current. The information forming the electric field will quickly spread around the conductor in the form of electromagnetic waves. The speed of this electromagnetic wave transmission is close to the speed of light. This is the true "speed of electricity".

Why is the speed of electricity the same as the speed of light?

From the previous analysis we can draw the conclusion: what we call the speed of electricity is basically the speed of electromagnetic wave propagation.

Here’s the key: light, which has always occupied the top spot in the speed rankings, is a kind of electromagnetic wave, but it can be seen by us.

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