Two models of Electrical current?

Question

I am a bit confused about the exact nature of electric current flow.

Is electric current due to excess of electrons on the negative terminal of the cell/battery and these electrons leave terminal, flow through the conducting wire, reach the positive terminal (where there is electrons deficiency) of the cell/battery and and fill the gap

OR

The Cell, due to the electric field, sets up the conducting wire's electrons (not the ones in the chemical of the cell) move with a slow drift speed while electrical energy travels at the speed of light? or could it be viewed both ways?

I would appreciate a very clear detailed answer for this question kinnda bothers me a lot.

Answer 1

both are correct, kinda.

Current is the movement of charge; in the case of copper conductors, that means it's electrons on the move.

Why do they move? because of a difference in POTENTIAL (or voltage). There are too many electrons in one place relative to another, so in the search for equilibrium that is nature's never-ending obsession, the electrons will move from one to the other, if they can get there.

The strength of the electric field is not really what is driving them along. Electric field strength is important with insulators, because it tells you how much stress the insulator is under. Too much stress and it will break down and start conducting, and then it's voltage that drives the current.

But... what happens when charged particles move? they create changes in electric fields. Those changes travel as electromagnetic waves along the conductors, at the speed of light, setting other electrons along the wire into motion as they go. So even though the movement starts at one location (the switch), within a light-speed sprint, the electrons throughout the length of the wire are in transit. That's what the electric field is doing for you - transmitting the information that says "move your sorry asses". It also transmits the energy (in case you were actually planning on doing something useful with your electricity).

Answer 2

In solid conductive metal, with no external forces applied, there exists a random motion of free electrons created by the thermal energy that the electrons gain from the surrounding medium. When an atom loses a free electron, it acquires a net positive charge. The free electron can move amongst these positive ions, while the positive ions can only oscillate about their mean fixed positions. The free electron is therefore the charge carrier in a typical solid conductor. Given an imaginary plane through which the wire passes, the number of electrons moving from one side to the other in any period of time is exactly equal to the number passing in the opposite direction.

When a wire is connected across the two terminals of a DC voltage source such as a battery, the source places an electric field across the conductor. The moment contact is made, the free electrons of the conductor will drift toward the positive terminal under the influence of this field. For every ampere of current, 1 coulomb of electric charge (which consists of about 6.242 × 1018 electrons) drifts every second at the same velocity through the imaginary plane through which the conductor passes.

Answer 3

The model I found the easiest to work with was to imagine the positive terminal of the cell has many positve ions (positively charged molecules). Electrons are attracted to these postive ions, and start "jumping" from nearby neutral atoms towards the positive ions. The atom an electron jumps from now has one fewer electron, and is therefore itself positively charged. Now an electron from a neighbouring neutral atom (further away from the terminal) is attracted, and so on.

The electrical field is due to the current, not the other way round. Note that the speed of an electrical signal is not related to the speed of the individual electrons - the speed of the signal can be thought of as a wave function which is carried by the electrons, which are themselves travelling more slowly. It's a bit like if you throw a stone into a river - the rate at which the ripples spread is unrelated to the speed of the river itself.

Answer 4

You're sort of asking two questions - or asking about two different phenomena of DC current. A good example of a DC electrical circuit is a hoola hoop filled with marbles. (Well, maybe not an ideal one, but good.) cut the hoola hoop, and stuff one marble in. This makes you the battery, BTW. The marbles are the electrons, and the hoop's the circuit. As you push a marble in, another one pops out the other side. The more power you put into this, the faster the marbles travel, and the faster they reappear at the other end. The cell provides the electrical energy to um, stuff marb - er, electrons into the circuit.

Answer 5

Electrical current is the flow of electrons, or perhaps more accurately, the flow of the "holes" created by a vacating electron. The electron movement can be created chemically, as in a battery, or magnetically, as in a generator. I think.

Answer 6

Both are correct but, BUT, the electrons moves from one atom to another at high velocity, at speed of light. one electron leaves its atom, of the wire, or one of the atom releases one of its electron, and remains avid (longs) other electron, to fill his hole, and catch the one of neighbor atom. Thus, forms a large flow across the conductor wire, at light speed.