Copper is a good conductor because the outer most electrons from the nucleus are weekly bound and repulsive, such that a small perturbance, like a potential difference between two ends of a wire, can knock the valence electrons from an atom free, which then perturb the neighboring valence electrons and so on resulting in a cascade disturbance of moving charges or current throughout the material. The energy required to free the valence electrons is called the band gap energy because it is sufficient to move an electron from the valence band or outer electron shell, into the conduction band where upon the electron may move through the material and influence neighboring atoms.
The above following diagram illustrates this concept. Insulators are materials where the electrons are not able to freely move. Examples of good insulators are: rubber, glass, wood,. A battery converts chemical energy into electrical energy by a chemical reaction. Usually the chemicals are kept inside the battery. It is used in a circuit to power other components. A battery produces direct current DC electricity electricity that flows in one direction, and does not switch back and forth as is with AC alternating current.
For more information on Batteries see: How does a Battery Work? A generator usually means a machine that makes electrical energy. It has a generator head with wires, spinning inside a magnetic field. The resulting electromagnetic induction makes electricity flow through the wires.
For this reason, some people say that the magnitude squared of the wavefunction is the only real entity, whereas the original wavefunction itself is just a mathematical crutch that is needed because our theory is inelegant. Is the magnitude squared of the electron wavefuntion the real physical entity or is the original wavefunction the real physical entity?
This question is really a philosophical one and not a physical one, so I will not pursue the question here. To scientists, the question, "What is actually real? We are more concerned with making the equations match the experiments. So what does all this have to do with an electron in an atom? The point is that an atomic electron's raw wavefunction does vibrate, but the magnitude squared of the wavefunction does not vibrate.
In fact, physicists call stable atomic electron states "stationary states" because the magnitude squared of the wavefunction is constant in time. If you consider the raw wavefunction to be the truly physical entity, then you have to say that an electron in an atom experiences motion in the form of a vibration. If you consider the magnitude squared of the wavefunction to be the truly physical entity, then you have to say that an electron in an atom experiences no vibration, and therefore no motion.
I consider the first choice to make more sense. You can mathematically show that certain atomic electron states contain angular momentum i. It's hard to make sense of the claim that an atomic electron contains angular momentum and at the same claim that the electron is completely motionless in every sense of the word.
For this reason, I prefer to view the raw wavefunction as the truly physical entity, and therefore an electron in an atom experiences motion in the form of vibrations. But, again, the question, "What is actually real? The bottom line is that the raw wavefunction of an electron in a stable atomic state experiences vibrational motion.
Likewise the electron can be found in any position in that little cloud if something comes along to measure the position to that accuracy.
If that sounds mysterious, it is. I've heard that electrons don't collapse in on the nucleus because the trajectory that they take around the nucleus must be an integer of their wavelength, or else they will destructively interfere with themselves. Thus their wavelength, which is proportional to their energy, prevents them from collapsing, because in order to radiate energy, the energy must be given off at a certain rate, which would cause the electron wave to destructively interfere with itself.
My question is where do electrons get their kinetic energy, and thus their wavelengths from, and, if that wavelength theory is true, how can they be lowered back to their orininal energy level after being elevated by a photon, since that would cause destructive interference? John- Those things you've heard are often taught in school and pictured in popular science shows. Nonetheless they are false or too vague to be useful.
Electrons in atoms, like all objects on a small scale, show quantum properties which cannot be pictured in any familiar way. They don't have either a particular wavelength or a particular position. The explanation of why the electrons don't collapse in further toward the nucleus is more like this. In classical physics, a particle can have any kinetic energy regardless of what position it's at, but not in quantum mechanics.
The kinetic energy is determined by the shape of the same 'wave-function' which also represents the probable positions of the particle. If the wave is scrunched in tightly, the kinetic energies it represents are big. So when a wave starts scrunching in close to the nucleus, its kinetic energy goes up more than its potential energy goes down.
The ordinary atomic size minimizes the total energy. That would be a big problem if somehow there was a way for the electrons to start with zero energy. If an electron is floating around on its own, its kinetic energy can be very low. However, there is then a lot of electrostatic energy associated with its electric fields.
That can be lowered by bringing it closer to a positive charge, like a proton. That can form a simple hydrogen atom. The electron will now have more kinetic energy, but less potential energy. The extra energy will radiate away as an electromagnetic field.
What is the property of a particle that enables particles to be accelerated by a potential difference - Alex age 17 Aus. It's electric charge. A potential difference is measured in Volts. A particle with charge equal to that of an electron will experience a 1 eV increase in energy for a 1 V increase in potential. An alpha particle, with charge twice that of an electron, would get 2 eV increase in energy, etc.
Since this quantity has an algebraic sign you can both accelerate and decelerate charged particles. By the way, one electron volt is equal to 1. I'm not here to ask a question but make a statement on this subject. See, the problem with Quantum Physics is that they don't take into account the universe.
The universe is moving and so is the matter inside of it for one basic reason; we are in a black hole. The reason the electron is moving, because we are moving in a shape of a vortex. The most important question that most teachers and professors don't address when it comes to atoms is, why do positive charges stick together? The answer is: Gravitational Singularity.
If you think of earth as being an atom and people as the electrons, the people are pulled towards the core of the earth, but due to the distance the force is weak, and we are able to move around and continue with our daily lives.
It's the same case with the atom; gravitational singularity at the core of the atom is what's holding the protons together, and allowing electrons to stay in orbit. Ok, since you don't have any questions, I do. Do you have any shred of evidence for any one of those assertions? Are you able to calculate any actual measurable physical quantity, like those which are calculated using quantum theory, including the attractive nuclear force?
Why do electrons move like a wave? Okay, I've read the answers that have been proposed to the questions. If I get it correctly, the reason why electrons do not collapse on the protons is because the potential and kinetic energies settle into a happy medium and thus do not send the electron pinwheeling into the nucleus. But one thing I would like to ask is how do the potential and kinetic energies prevent the electron from careening into the nucleus?
What are the mechanics of these energies that act on the electron? I think there's one key ingredient here that isn't close to what one would guess based on classical mechanics. It's that the kinetic energy of the electron wave depends on its shape. Specifically, it goes as the second derivative of the wave function with respect to spatial coordinates. That means that the only way to get a small kinetic energy is to have a wave which varies only slowly as a function of position.
However, in order to be concentrated in a small region needed to lower the potential energy the wave obviously must vary rapidly as a function of position. That's why there is a trade-off. How is it that as you said in a hydrogen atom the electron exists in a cloud around the nucleus? Isn't it just one electron?
Why is it a "cloud" around the nucleus and not like a planet around a star? Yes, it is just one electron. The point, however, is that an electron is not what you think it is. It really is a smear, not a dot.
That smear can, under some conditions, by pulled into a small region or under other conditions expanded out to a large region. So far as we can tell, that's all there is to it.
As for the idea that there's really a dot-like position hiding in there, as we discuss above, violations of the Bell Inequalities show that such pictures are false. From the point of view of the fundamental equations of physics, the mystery if any is not how an electron can be spread out but rather how the planet can be not spread out.
From the previous answers given I see no explanation for the perpetual motion of the electron? As far as I can tell Quantum Mechanics does not explain the motion of any particle? It says that electrons are smears or clouds. I find this abstact mathematical explantion very unsatisfatory. I think that the most honest answer that can be given by a physicist is they don't really know what causes the motion of particles.
So I will rephrase the question. Why is an electron not stationary? What is the mechanical explanation for its movement? Equally important is it really a cloud of probabilites or an actual physical object that is impossible to measure in our laboratories. Since at this time in history we cannot determine the actual location and momentum of an electron why have we have settled for the pseudo explanation of a probability cloud as the explantion of electron motion?
You're nostalgic for a world of mechanical parts. Any mechanical model- in fact, any model which has any local realist description- must obey mathematical relations called the Bell Inequalities.
Unfortunately, a wide variety of experiments give results flatly inconsistent with these inequalities. You may believe that relativistic quantum mechanics is a "pseudo-explanation".
Nonetheless it is spectacularly successful at predicting experimental results. For example, it predicts the electron's gyromagnetic ratio the ratio of an electron's magnetic moment to what would be expected in a simple classical picture to within ten decimal place accuracy.
We can't get around those mysteries by pretending we don't know what we know experimentally about the small scale. They have "orbits" similar to how electrons have orbits. They fill the orbits differently than electrons, but the same idea. They also form collective modes that either vibrate or rotate.
Do electrons move like waves? Remember, an electron behaves like a wave as it travels, and an electron wave can easily pass through both slits at the same time, just as a water wave could. Each individual electron "knows" about the interference pattern, since the pattern can be built up by electrons passing one at a time through the slits.
Does the nucleus of an atom spin? Subatomic particles electrons, protons and neutrons can be imagined as spinning on their axes. In many atoms such as 12C these spins are paired against each other, such that the nucleus of the atom has no overall spin. However, in some atoms such as 1H and 13C the nucleus does possess an overall spin.
How do atoms move? Atoms can also vibrate, due to interaction with electromagnetic fields, getting polarized. Objects in motion tend to stay in motion due to their inherent inertia, so atoms that are moving will remain moving in the same direction and speed. Do electrons rotate in circular paths around the nucleus?
The Bohr atomThe electron travels in circular orbits around the nucleus. The orbits have quantized sizes and energies. The laws of quantum mechanics describe the process by which electrons can move from one allowed orbit, or energy level, to another. Why do electrons circle the nucleus?
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