Matter is made up of small units called atoms. At this atomic level matter possesses two basic characteristics. Matter has mass and it may have an electrical charge, either positive, negative, or it could be neutral with no charge. Each atom contains three types of particles with different characteristics; positive protons, neutral neutrons, and negative electrons. Electric current electricity is a flow or movement of electrical charge.
The electricity that is conducted through copper wires in your home consists of moving electrons. The protons and neutrons of the copper atoms do not move. The actual progression of the individual electrons in a given direction through the wire is quite slow. The electrons have to work their way through the billions of atoms in the wire and this takes considerable time.
In the case of a 12 gauge copper wire carrying 10 amperes of current typical of home wiring , the individual electrons only move about 0. If this is the situation in nature, why do the lights come on so quickly? At this speed it would take the electrons hours to get to the lights. Atoms are very tiny, less than a billionth of a meter in diameter. The wire is "full" of atoms and free electrons and the electrons move among the atoms. 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.
We want to know which is faster: electricity or light? Answer 2: Suppose Ismael is on earth and Mariela is on Mars. Ismael light bulb Find out the distance between Earth and Mars. But this "guiding" of light along the wires makes it slow down little.
Answer 3: Light travels through empty space at , miles per second. Answer 4: It is very difficult to distinguish electricity from light. A guy named Maxwell,a creative physicist,developed the theory and first understood the relation between electricity and light. He was a true giant of science and physics.
Maxwell's equations are fundamental to modern science and technology especially as it relates to electricity, electronics, lasers, radio waves, light etc. In order to understand each of these speeds and why they are all different and yet physically meaningful, we need to understand the basics of electric currents. Electric currents in metal wires are formed by free electrons that are moving. In the context of typical electric currents in metal wires, free electrons can be thought of as little balls bouncing around in the grid of fixed, heavy atoms that make up the metal wire.
Electrons are really quantum entities, but the more accurate quantum picture is not necessary in this explanation. When you add in quantum effects, the individual electron velocity becomes the "Fermi velocity".
The non-free electrons, or valence electrons, are bound too tightly to atoms to contribute to the electric current and so can be ignored in this picture. 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.
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