Each free electron in the metal wire is constantly flying in a straight line under its own momentum, colliding with an atom, changing direction because of the collision, and continuing on in a straight line again until the next collision. If a metal wire is left to itself, the free electrons inside constantly fly about and collide into atoms in a random fashion.
Macroscopically, we call the random motion of small particles "heat". The actual speed of an individual electron is the amount of nanometers per second that an electron travels while going in a straight line between collisions. A wire left to itself carries no electric signal, so the individual electron velocity of the randomly moving electrons is just a description of the heat in the wire and not the electric current.
Now, if you connect the wire to a battery, you have applied an external electric field to the wire. The electric field points in one direction down the length of the wire. The free electrons in the wire feel a force from this electric field and speed up in the direction of the field in the opposite direction, actually, because electrons are negatively charged.
The electrons continue to collide with atoms, which still causes them to bounce all around in different directions. But on top of this random thermal motion, they now have a net ordered movement in the direction opposite of the electric field. The electric current in the wire consists of the ordered portion of the electrons' motion, whereas the random portion of the motion still just constitutes the heat in the wire. An applied electric field such as from connecting a battery therefore causes an electric current to flow down the wire.
The average speed at which the electrons move down a wire is what we call the "drift velocity". Even though the electrons are, on average, drifting down the wire at the drift velocity, this does not mean that the effects of the electrons' motion travels at this velocity.
Electrons are not really solid balls. They do not interact with each other by literally knocking into each other's surfaces. Rather, electrons interact through the electromagnetic field. The closer two electrons get to each other, the stronger they repel each other through their electromagnetic fields.
The interesting thing is that when an electron moves, its field moves with it, so that the electron can push another electron farther down the wire through its field long before physically reaching the same location in space as this electron. As a result, the electromagnetic effects can travel down a metal wire much faster than any individual electron can.
These "effects" are fluctuations in the electromagnetic field as it couples to the electrons and propagates down the wire. However, is it possible for Ismael to see the light at the same time as Ismael? It is impossible for him to see it at a different time! Electricity is just Light guided along wires. Sort of. Light travels through empty space at , miles per second. Part of the reason is that light is massless; it has no weight, whereas the electricity flowing in the wires is made up of a stream of electrons, all of which have some small amount of weight.
In addition, the electrons flowing through the wires constantly bump into the atoms of the wire, which slows them down considerably. If you were to take the electrons out of the wire and make them flow through space which is essentially what you do when you make a spark , they can move faster, but no matter what, they cannot move as fast light.
Optical radiation called light is the same thing as x-ray radiation is the same thing as microwave radiation is the same as infrared radiation is the same as radio waves. They are all caused by alternating electric charge or electric current.
In free space the radiation travels at the "speed of light" but the radiation can also travel down two wires at the speed of light unless the two wires are surrounded a dielectric like plastic. Electricity is a fascinating topic for young and old alike. How fast is this? Picture this: If you were as fast as electricity, you could travel around Earth eight times in the time it takes someone to flip on a light switch!
Because the speed that electricity travels is so fast, the effects of electricity are immediate once you come in contact with it. You may think you can pull away from an electrical shock to avoid injury, but due to the speed, there is no chance of shock avoidance. When a person comes in direct contact with a strong electrical current, like from a live household wire, their muscles tighten in such a way that they are physically unable to let go or release from the source.
Even touching someone who is being shocked is highly dangerous and can pull you into the electrical circuit. The human body is a strong conductor of electricity. Because electricity flows quickly through water, and the human body is composed of 70 percent water.
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