We now know particles seek and exchange energy and we know how electrons act as energy collectors for protons and so have near matched numbers in structures. To effectively perform their role electrons seek their own energy gathering space and keep at a distance from other electrons by exchanging energies with them. The outer electrons of atomic structures are not so much energy bound to the protons of a single atom. They are responsible for the covalent, ionic and metallic bonds that make for and provide the energy links of extended structures.
In metallic bonding outer atom electrons repetitively move their energy links to protons of different atoms. I think such wandering electrons, often referred to as an electron gas, go in search of a more efficient particle energy arrangement but never find it. In metals it takes only a tiny amount of energy to move an outer electron’s energy link from one atom nucleus to another atom nucleus but each bond formed is strong and gives metals their considerable strength. In no way should we think of these wandering electrons as free. Easy to move between atoms but not free.
Silver, copper, gold and aluminium are described as good conductors because their outer electrons can be most easily encouraged to move between atoms. We often describe such elements as low resistors because it takes little energy to move outer electron energy link from one atom to another. Electrons like their own space away from other electrons and exchange energies to achieve that. It is why electron moves trigger other electron moves.
If we create an electron surplus at one end of a piece of wire (the negative battery wire in the diagram) we push electrons that don’t want to be near one another in the wire closer together. The electrons cannot break free of the wire as the surround air does not want them and the switch will not allow their further movement along the wire as air is a high resistor.
Alternatively if we create a deficit of electrons at one end of a wire (the battery positive wire) outer electrons are encouraged to move into electron spaces, often referred to as holes, in the wire where they satisfy surplus proton energy needs. The outer electrons spread themselves more thinly in the wire.
Close the switch in the above circuit and the pressurised electrons on the negative side of the switch are able to move and better satisfy the energy demanding proton surplus on the positive side of the wire. The circuit enables electron motions as delivered by their photon energy exchanges throughout the whole of the circuit. Wire protons only limit the movements of electrons when they are not getting their energy needs and in our circuit protons losing electrons quickly get another one.
Be clear, electrons do not move at high speed. They may move rapidly between atoms but their progress along a circuit wire is slow. It is the light speed photon energy exchanges between the electrons that deliver electron motions throughout the circuit and so put lights in a circuit on almost instantly.
Electrical current is measured in amps. One amp equates to 6.25 billion, billion electron movements past a wire location every single second. That is a lot of electrons in motion but it is only about the number of outer electrons in one tenth of a millimetre of a suitable diameter wire. We can calculate electron progress along a wire in such circumstances. It is as low as one half of a metre every hour. Tortoises move faster than that.
Tungsten particle structures in the light bulb filament of our circuit do not easily give up their outer electrons. The tungsten protons hold onto their outer electrons more than copper protons do. Removing a tungsten outer electron from its atom requires a build up of the photon energy pushes of many copper electrons or the energy desires of many protons in need of electrons. Up close electron photon pushes are always more effective than the more distant proton photon energy desiring pulls, a feature much evident in semi conductor technology.
Tungsten electrons removed from their parent atoms have been subjected to higher yhan normal energy exchanges and have gained some mass energy. They seek a new atom home and rapidly find one and release their gained energy as photons of visible light and infra red heat. The visible light photons reach surround objects that absorb them and emit other photon energies that we can see. If we look at the bulb we can see some of the radiations coming from it. Many of the infra red heat photons emitted are absorbed by other particles of the tungsten element. These higher than normal photon energy exchanges cause the tungsten to get very hot. To stop the tungsten burning we exclude oxygen by encasing it in a glass vacuum.
Copper outer electrons that are pressured into moving in an electrical circuit also release energy when they re-engage with atoms. Their energy releases are small and almost unnoticeable but warm the wire. It might seem that the surround air remains uninfluenced by the energy changes in the wire but that is not so. Air electrons move within their structures in response to the wire electrons but they are not removed from those structure. Air is not a good conductor and only in situations like lightning strikes will air part with electrons.
Voltage is the photon drive that causes electron motions that become a cascade motion as a result of the photon energy exchanges between electrons. Such energy transfers happen in your mobile phone circuits, in car circuits and in the lengthy wired circuits that bring electrical energy to our homes from power stations hundreds of miles away. It is electron movements in an appliance that provide photon energies that deliver our energy needs and it doesn’t matter whether those electrons have a directional movement or a to and fro movement, as with our mains alternating supplies. They still involve energy exchanges.
There are many electrical devices and so it might seem strange that I now choose to show how a capacitor works. I do so because a capacitor illustrate how energy can be stored in a structure, but also because capacitor energy stores are much more common than you might realise. The mobile phone you hold to your ear may have more than 500 tiny capacitors in it and your television or camera would not work without them.
Capacitors comprise of two metal plates with an insulating material between them called a dielectric. They are often cylindrical in shape as the plates are coiled up to save space. Connect a battery energy source to a capacitor and a short duration decreasing current flows that creates high levels of electron shortages at the positive plate and high numbers of extra electrons at the negative plate. Electrons do not move between the plates but their photon energy exchanges act linearly across the plates and influence the dielectric insulating material.
That dielectric material does not part with its electrons but its particle structures are distorted by the photon pressures. The dielectric is said to be polarised and there is much more energy being exchanged by its particles. The particles are being held in a more agitated energy storing state and they would like to revert to a lesser energy state. Disconnecting the battery from the capacitor does not change the situation as the stored energy has nowhere to go but connect a circuit to the capacitor and it acts as an energy supply until its dielectric and plate particle energy exchanges return to more desirable less distorted energy states. Capacitors are much used in alternating voltage situations to smooth out energy flows.
It is opportune here to consider what voltage is. It is a measure of the pressure on photons to move between two points. Such pressure is transmitted along a circuit by photon energy exchanging electrons and resisted by proton energy holds on those electrons. A voltmeter actually measures the effectiveness of its push between any two points by measuring the electron flow between those points through a very high known resistance.
We saw in the last article how we could calculate mechanical energy by multiplying force by movement. We learnt how mechanical force is due to interacting photon pressures between particle structures and of course distance moved is that of particle structures. In this article we have learnt how voltage provides the photon interactions between electrons and that they are what is being pushed. Total electron particle movements are the rate of electron particle movements (current) x time and that is why electrical energy in joules can be had by multiplying volts x amps x time.
At this stage I hope you start to see that although aspects of energy seem to be wildly different they are fundamentally the same.