Why is the conduction velocity of electric current equal to the speed of light? Why is the propagation velocity of electric field equal to the speed of light C?

Why is the conduction velocity of electric current equal to the speed of light? Why is the propagation velocity of electric field equal to the speed of light C?

Light is a kind of electromagnetic wave. Light has wave particle duality. Many things in nature are electromagnetic waves, such as α, β rays and the orientation of free electrons

Why is the current conduction rate equal to the speed of light?
Why does the electric field build up everywhere in the circuit at the speed of light C in vacuum?

In a circuit, the conduction velocity of the current is not the velocity of the electron, but the propagation velocity of the electric field. The propagation velocity of the electric field is equal to the speed of light C. light is only a part of the electromagnetic field, and the velocity of the electromagnetic field is 300000000m / s. therefore, the electric field is not established at the speed of light C, but the transmission velocity of the electric field is the king. The electromagnetic field contains light~

Why is the speed of electric current the speed of light
It's not because the photon's mass is very small that the speed of light can be achieved. Although the electron's mass is also small, the relative photon's mass is very large. It needs huge energy to achieve the speed of light

The propagation speed of light is the moving speed of photons, while the propagation speed of electricity refers to the propagation speed of electric field (some people say it is the propagation speed of electrical signal, but it is the same), not the moving speed of electrons. The electrons in the wire can move several meters per second (macro speed) is already a very high speed
The propagation speed of electric field is very fast. In vacuum, the speed is close to the speed of light
The propagation process of "electricity" is roughly as follows: before the circuit is connected, although there are free electrons everywhere in the metal wire, there is no electric field in the wire, and the whole wire is in the state of electrostatic balance. The free electrons only do irregular thermal motion without directional motion. Of course, there is no current in the wire. As soon as the circuit is connected, the electric field will send the information of field source change, It spreads out at about the speed of light, so that an electric field is rapidly established in the wires around the circuit, and the electric field pushes the local free electrons to drift and form a current. It is a misunderstanding to think that after the switch is turned on, the free electrons start from the power supply, move in a direction at the drift speed, and reach the lamp before the lamp can be on