Naked Science Forum
Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: mxplxxx on 31/05/2014 06:13:10
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Pretty basic question I know "how is water heated?" but I don't actually have an answer. Presumably via "heat" photons (does such a beast exist?). So what do the heat photons interact with? With the hydrogen atom, with an electron, with an oxygen atom? With a quark within one of the atoms? Given its quantum nature, the photon cannot interact with more than one of these at once. So we have (say) a hydrogen atom that has been energised via a photon. How does this affect the water molecule as a whole? What does energised mean anyway. If speeded up, how can it do so given that it is constrained by molecular forces? What determines which atom/electron the heat photon interacts with? Why does a "heat" photon not pass through the water molecule as a light photon does? I await with interest for some replies.
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There are many types of heating & heat transfer.
Conductive heat transfer
Radiative heat transfer
Convective heat transfer
Phase Transition (evaporative) heat transfer
If you are talking about a hot water heater or a pot on the stove, the majority of the heating will be with direct conduction, and some convection stirring the pot.
Light (photons) comes in many different frequencies. Many substances may be transparent to some frequencies, and opaque to other frequencies. So, you might have colored glass that transmits some light, but not all light.
Pure water is fairly transparent to light, but will absorb infrared and UV.
Radiative heat isn't just limited to IR. However, earth temperatures radiate in the IR spectrum, while the much hotter sun radiates heat in the visible spectrum. Photons of any wavelength will generate heat when absorbed.
As far as what absorbs the photons, I think it is the electrons, but also has to do with resonance of the bonds.
It has been years since I've done any IR spectroscopy, but you can take two similar substances such as benzene vs toluene, and they will have several of the same IR absorption peaks, but the CH3 substitution will add a few additional peaks. Then each peak can be identified as stretching or bending of the specific covalent bond.
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Energy has many forms, but energy is force. Electromagnetic force made up mater, movement and changes in all things.
When you boiling water with fire, the fuel atoms and oxygen exchange electron bond structure and produce vibration between electron and nucleus and atoms, the vibration transfer from fire to water container, the atoms of the container start to vibrate and transfer vibration to water. Temperature is the strength of vibration.
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Energy has many forms, but energy is force.
No. Energy isn't force. Energy (joules) is expended to apply force (newtons).
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"heat" photons (does such a beast exist?)
When you feel heat from a fire or the Sun, most of this energy is in the form of infra-red radiation (IR), which is a form of light, and does come as photons.
These photons start the water molecules in your skin vibrating more vigorously, which can be measured as an increase in temperature. This triggers heat-sensitive nerves in your skin to relay the feeling of warmth to your brain.
So what do the heat photons interact with?
The IR photons are emitted with a wide variety of frequencies, but just a limited range of frequencies will match vibration frequencies of a water molecule, and be strongly absorbed. These start the water molecules spinning, wobbling and jumping in and out (imagine a water molecule with springs between the oxygen and hydrogens - then think of every way this thing could wobble).
Why does a "heat" photon not pass through the water molecule as a light photon does?
Some frequencies are absorbed by water. Other frequencies will pass straight through, and not contribute to the warming effect.
If, however, the water is held in a blackened pot, the soot on the pot will absorb almost all IR and visible frequencies, and turn more of the incoming radiation into hot water. (On the other hand, this black surface will also be more effective at radiating this heat back into the environment, so this is a tradeoff.)
"heat" photons vs phonons
Photons will pass through a vacuum (eg from the Sun) before heating the water. This is the mechanism of heat radiation.
With a fire or an electric stove, we don't intentionally place a vacuum between the heat source and the water; in fact, vacuum is a pretty good insulator - it is one of the layers of insulation in the "thermos" flask that can hold hot and cold liquids.
With a pot on an electric stove, the electrons in the electric current run into atoms in the heating element, causing them to vibrate. These vibrations can travel through the solid element as "phonons", the quantum of sound (by analogy with photons, which are the quantum of light). These phonons can pass through the pot. When they strike the molecule of water, the phonons make the water molecule vibrate, which increases its temperature. This is the mechanism of heat conduction.
With a pot suspended above a fire, the vibrations of the hot gases released by the fire reduce the density of the air, so it rises towards the pot. This is the mechanism of heat convection. These molecules bump into the pot, transferring energy through the pot as phonons, and heating the water (as described above).
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Photon is a invented word, there is no photon but electromagnetic wave.
Space is charged, wake up.
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Photon is a invented word, there is no photon but electromagnetic wave.
Space is charged, wake up.
perhaps you would like to give us a list of words that are not made up.
Also, space isn't charged- we would notice.
And how do you explain things like Compton scattering and the photoelectric effect
However, as those will all be speculation, please make any further comments in a thread in the right forum.
Don't clutter up this thread with stuff you are making up.
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Things can learn from books, can learn from thinking and watching.
They cannot explain why electrons not stick to the protons, invented a theory called what?
Photoelectric, when electromagnetic wave hits atom, if the force is strong enough, electrons will be knock out. Wave has force, no need to invent a photon to knock out electron.
If the space is not charged, matter will not form, force will not transfer. The universe is an electromagnetic field. Matter is locally condensed part of the whole field.
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perhaps you would like to give us a list of words that are not made up.
pa, ma, hahahahahahahaha
Also, if space is charged- we would notice.
If it is wrote in school book, we will.
The charge is leveled everywhere besides near matter, hard to noticed.
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Two of those seem to be words made up by children and the last isn't exactly "made up" it's an attempt to mimic something.
Incidentally, you were also wrong about this
"Temperature is the strength of vibration."
And you are wrong about this too
"Photoelectric, when electromagnetic wave hits atom, if the force is strong enough" but I will leave it to the Mods to split this thread into your personal beliefs and the mainstream world of science before I explain why you are wrong about that.
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1972 or so, my physics pro told the whole class, that he worked with a Japanese pro to discovered a new particle, if I remembered right, k particle. The Japanese pro got a nobel prize for it. But the data to proof the theory/math was all fake. The tested data was far from the theory predicted.
I believed him, do you? What is meanstream? Christainism?
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Not a great fan of "vibration" which never gets explained to my satisfaction. How about this? The rest-mass energy of a water molecule is fixed. A water molecule can be speeded up ("heated") or slowed down ("cooled") but only as a whole entity i.e. individual atoms/electrons cannot have their speed varied. This can happen if a water molecule acts as a frame of reference as per Einstein's relativity. A photon interacting with this frame of reference exchanges time (or power if you like, but not energy) with the frame of reference (water molecule) causing it to speed up/down. This way the photon is either cooled down (looses power) or heated up (gains power) and vice versa for the water molecule and the total energy of the system stays the same. Simple and elegant n'est pas (if you accept the premise that time is exchangeable) !?
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Not a great fan of "vibration" which never gets explained to my satisfaction. How about this? The rest-mass energy of a water molecule is fixed. A water molecule can be speeded up ("heated") or slowed down ("cooled") but only as a whole entity i.e. individual atoms/electrons cannot have their speed varied. This can happen if a water molecule acts as a frame of reference as per Einstein's relativity. A photon interacting with this frame of reference exchanges time (or power if you like, but not energy) with the frame of reference (water molecule) causing it to speed up/down. This way the photon is either cooled down (looses power) or heated up (gains power) and vice versa for the water molecule and the total energy of the system stays the same. Simple and elegant n'est pas (if you accept the premise that time is exchangeable) !?
Do you believe the structure of atoms? Are electrons really constantly moving around nucleus?
Think an electron is bounded with proton by a spring to form hydrogen, then think vibration. check out this toy, it explains the neture about the spring.
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Not a great fan of "vibration" which never gets explained to my satisfaction.
Vibrational modes of a molecule are visible in its Infra-Red spectrum, and also affects the specific heat (http://en.wikipedia.org/wiki/Heat_capacity#Theory_of_heat_capacity) of gases (in the liquid phase, the specific heat of water is dominated by its electrical dipole, rather than by its geometry).
Some nice animations of atomic vibrations here: http://en.wikipedia.org/wiki/Infrared_spectroscopy#Number_of_vibrational_modes
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Not a great fan of "vibration" which never gets explained to my satisfaction.
Vibrational modes of a molecule are visible in its Infra-Red spectrum, and also affects the specific heat (http://en.wikipedia.org/wiki/Heat_capacity#Theory_of_heat_capacity) of gases (in the liquid phase, the specific heat of water is dominated by its electrical dipole, rather than by its geometry).
Some nice animations of atomic vibrations here: http://en.wikipedia.org/wiki/Infrared_spectroscopy#Number_of_vibrational_modes
I wish my balls are blue like those.
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Not a great fan of "vibration" which never gets explained to my satisfaction.
Vibrational modes of a molecule are visible in its Infra-Red spectrum, and also affects the specific heat (http://en.wikipedia.org/wiki/Heat_capacity#Theory_of_heat_capacity) of gases (in the liquid phase, the specific heat of water is dominated by its electrical dipole, rather than by its geometry).
Some nice animations of atomic vibrations here: http://en.wikipedia.org/wiki/Infrared_spectroscopy#Number_of_vibrational_modes
Thanks. Being a software developer, I try and understand physics by developing simulations of the problems I study. If I can't simulate a problem it is invariably because the problem is poorly defined and/or understood in the physics community. This is an all too common event. Very few problems in physics address the "how" question. They tend to go from "what" to results via hard-to-understand mathematical equations. So it seems to be with molecular vibration. In the case of this post I am looking at finding out the low-level process by which water is heated up (e.g. the hydrogen atom absorbs a photon and it accelerates in the direction of ... etc.). I have nothing I could program a simulation on. All I am getting is high-level jargon that means nothing to me.
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Before simulate heat transfer, simulate matter structure first. Without clear understanding atomic structure, the rest is fogy.
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Another common method of heating water was not directly mentioned above: the microwave oven (http://en.wikipedia.org/wiki/Microwave_oven#Principles).
Many molecules (such as those of water) are electric dipoles, meaning that they have a partial positive charge at one end and a partial negative charge at the other, and therefore rotate as they try to align themselves with the alternating electric field of the microwaves. Rotating molecules hit other molecules and put them into motion, thus dispersing energy. This energy, when dispersed as molecular vibration in solids and liquids (i.e., as both potential energy and kinetic energy of atoms), is heat.
Microwave heating is something that could be modeled, if you want to simulate a cup of coffee at the level of individual molecules. A cup of coffee has over 1027 water molecules, which will require over 1029 bytes of memory to store the positions of all the water molecules.
It may be better to start with simulating a small sample of water containing (say) 10-100 molecules with the individual electric charges (http://en.wikipedia.org/wiki/Water_model#3-site) on each oxygen & hydrogen atom, subjected to microwave radiation. Then extrapolate the temperature of this sample to the whole mass of water. This smaller simulation will easily fit into the 109 bytes of computer memory that can be economically purchased today.
But if you are interested in simulating a cup of coffee in a microwave , you can ignore the molecular-level events, and use a rough rule like "between 0.1C and 99.9C, it takes 4.2 Watts for 1 second to raise the temperature of 1 ml of water by 1C". (You need a different rule to describe what happens between -0.1C and +0.1C, or between 99.9C and 100.1C: see latent heat (http://en.wikipedia.org/wiki/Latent_heat).)
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Another common method of heating water was not directly mentioned above: the microwave oven (http://en.wikipedia.org/wiki/Microwave_oven#Principles).
Many molecules (such as those of water) are electric dipoles, meaning that they have a partial positive charge at one end and a partial negative charge at the other, and therefore rotate as they try to align themselves with the alternating electric field of the microwaves. Rotating molecules hit other molecules and put them into motion, thus dispersing energy. This energy, when dispersed as molecular vibration in solids and liquids (i.e., as both potential energy and kinetic energy of atoms), is heat.
Microwave heating is something that could be modeled, if you want to simulate a cup of coffee at the level of individual molecules. A cup of coffee has over 1027 water molecules, which will require over 1029 bytes of memory to store the positions of all the water molecules.
It may be better to start with simulating a small sample of water containing (say) 10-100 molecules with the individual electric charges (http://en.wikipedia.org/wiki/Water_model#3-site) on each oxygen & hydrogen atom, subjected to microwave radiation. Then extrapolate the temperature of this sample to the whole mass of water. This smaller simulation will easily fit into the 109 bytes of computer memory that can be economically purchased today.
But if you are interested in simulating a cup of coffee in a microwave , you can ignore the molecular-level events, and use a rough rule like "between 0.1C and 99.9C, it takes 4.2 Watts for 1 second to raise the temperature of 1 ml of water by 1C". (You need a different rule to describe what happens between -0.1C and +0.1C, or between 99.9C and 100.1C: see latent heat (http://en.wikipedia.org/wiki/Latent_heat).)
Thx Evan_au There will likely be a certain number of molecules at which the behaviour of the system will not vary when more molecules are added. There will also likely be abstractions (high level behaviour) available to reduce the number of states in the system. If you have watched the kayak events at the Olympics you would have seen how the water flows just about the same for each competitor. A body of water being heated will have swirls and eddies that may be able to be abstracted. The thing is, there are ways and means to reduce the total number of possible states of a system and still come reasonably close to the real thing.
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There are many ways to heat water such as absorbing light from the sun, sum of the energy going into the kinetic energy of the water molecules and that's what hot water is, i.e. when H2O molecules have a increase in their speed and thus kinetic energy.
Place a pan of water on the stove. When the fire is in contact with the metal the kinetic energy of the gas molecules from the fire is transfered through physical contact to the metal of the pan. Then the kinetic energy of the molecules and atoms which make up the pan is transfered to the H2O molecules and that's what it means for water to become heated.
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Pretty basic question I know "how is water heated?" but I don't actually have an answer. Presumably via "heat" photons (does such a beast exist?).
No, it doesn't. Every "normal" photon can heat a body. If you don't believe me, point a 100mW blue-light laser on your skin for 10 second and then tell me [;)]So what do the heat photons interact with? With the hydrogen atom, with an electron, with an oxygen atom? With a quark within one of the atoms?
Electromagnetic field interacts with every charged particle or even neutral, if it has an electric or magnetic moment. In an atom the first particles with wich EM field interact are the external electrons. If the EM wave' frequency is very high (X-Rays), it can interact with inner electrons; if it's higher (gamma-rays) it can interact with the nucleus.Given its quantum nature, the photon cannot interact with more than one of these at once
Why? It *can* interact with more than one, if its energy is high enough. Only that the energy released to every particle with which it interacts is quantized.. So we have (say) a hydrogen atom that has been energised via a photon. How does this affect the water molecule as a whole? What does energised mean anyway. If speeded up, how can it do so given that it is constrained by molecular forces?
It can affect the molecules in essentially 2 different ways: the first is to increase their average kinetic and potential energy while the molecules are still constrained (in this case the water's temperature increases); the second is to broke the constraint (water become liquid if it were solid or become vapour if it was liquid).
The fact water molecules can vibrate with greater average speed even if they are constrained is not difficult to understand: imagine two balls connected wit a spring. If you pull them apart of a little distance, the spring will be little stressed and when you release the balls they will start to vibrate gently, with little amplitude (maximum distance); if you pull them apart of a great distance and you release them, they will start to vibrate with a greater amplitude and so greater average distance (this greater *average* distance explains, simplistically, thermal expansion). What determines which atom/electron the heat photon interacts with? Why does a "heat" photon not pass through the water molecule as a light photon does? I await with interest for some replies.
The atom with which it interacts cannot be known before it does, if the EM wave extends for more than an atom's width.
A photon can "pass" or not through a water molecule, depending on the EM wave frequency: if the molecule (bond electrons, molecular dipoles, ecc.) doesn't "resonate" to that frequency, it will not absorb that photon. Actually is much more complicated than this (there is a "resonance" even in Rutherford scattering for example, but without any energy absorption from the EM field).
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lightarrow
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Energy has many forms, but energy is force. Electromagnetic force made up mater, movement and changes in all things.
When you boiling water with fire, the fuel atoms and oxygen exchange electron bond structure and produce vibration between electron and nucleus and atoms, the vibration transfer from fire to water container, the atoms of the container start to vibrate and transfer vibration to water. Temperature is the strength of vibration.
What I have coloured blue of your post is quite acceptable; you can forget the rest...
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lightarrow
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Photon is a invented word, there is no photon but electromagnetic wave.
Can you describe the "Antibunching" effect without using the photon concept?
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lightarrow
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They cannot explain why electrons not stick to the protons,
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You are not well informed: atomic electrons *can* be found on the proton: the 1s wavefunction ψ of the hydrogen atom's electron is non-zero in the nucleus; indeed, it has its *maximum* in the nucleus!
It's the |ψ|2 multiplied the *volume element* which is zero in the nucleus, non-zero in a specific region around it (range of distances) and still zero at greater distances. This because the volum element of a spherical layer at distance "r" is 4πr2dr.
Furthermore, remember that an electron is a quantistic system, not a "little ball" orbiting around.
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lightarrow
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Electron cloud dance around nucleus, the upper shell transfer vibration to the next shell and so on, that's how heat transfer works.
What stops electron jump on proton? Is there a fence protects nucleus?
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If vibrations are transferred by upper shells only, do nuclei stays in a fixed position?
It's the *entire* atom which moves (when it does, in heat transfer: in a phase transform, the atom's vibrations don't change, because the system's temperature doesn't vary) not the outer shell only.
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lightarrow
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We are neutral yet electrons jump on us from car doors sometimes.
How is it possible that electron not stick to proton all the time in atoms/matters? What force/matter/field seperates them apart? What's in between electron and nucleus?
Simple straight question, I find no answer that I understand yet, but I am sure there must be something other than empty space, to stop two opposite charges to stick together.
Space has invisible hands? Proton has defensive force field?
No. To be logically thinking, I suspect maybe space is filled with super tiny negative charged particles, each carries a fiction of an electron's charge.
Such particles responsable for forming nucleus/atom/matter, conducting EM wave, transfer force/energy.
Find a way to detect such particles, you know better ways. Maybe few books in physics could be rewrite.
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Photon is a invented word, there is no photon but electromagnetic wave.
Why on earth would you make such a claim? First off, as lightarrow indicated, all words are ”invented.” That’s where all the terms in physics come from.
Saying what you did implies that you don’t understand quantum mechanics. An electromagnetic wave is composed of photons so saying …, there is no photon but electromagnetic wave is quite misguided. It’s known that light is an electromagnetic wave. It’s also known that many metals emit electrons when light is shined on it. If electromagnetic field theory was correct then the energy from the EM field of the light would transfer energy to the electron which would then be able to over come the work function of the metal and fly off. However that takes time to happen according to EM theory is about 50 years. However its observed to happen nearly instantaneously. That’s how Einstein came up with the theory of photons and why he was awarded the Nobel Prize for it. Einstein spoke of “light quanta” something like that. I never read the original paper. I’ve been unable to find it in English.
However it wasn’t Einstein who coined the term photon. It was Gilbert Lewis who coined it in a letter to the editor in an article called Conservation of Photons in Nature, December 18, 1926, pages 874-875. He only coined the term. He didn’t know the true nature of photons when he wrote that paper. He thought of a photon as being an atom of light. He wrote
I therefore take he liberty of proposing for this hypothetical new atom, which is not light but plays an essential part in every process of radiation, the name photon.
When the theory of light became better understood the term photon was retained for the quantum of light.
Space is charged, wake up.
No, it isn’t. Why would you ever think such a thing? If it were then you’d most certainly know it. What sign of the charge do you think it is and why do think that we can’t detect it while we walk through it?
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We are neutral yet electrons jump on us from car doors sometimes.
How is it possible that electron not stick to proton all the time in atoms/matters? What force/matter/field seperates them apart? What's in between electron and nucleus?
The moon and the earth attract each other, so why doesn't the moon stick to the earth? Two objects can attract and still be in a stable orbital system where they don't collide. Electron orbitals are actually more stable than the moon/earth because of the laws of quantum mechanics provide some extra stability that is lacking in classical systems.
Simple straight question, I find no answer that I understand yet, but I am sure there must be something other than empty space, to stop two opposite charges to stick together.
Space has invisible hands? Proton has defensive force field?
No. To be logically thinking, I suspect maybe space is filled with super tiny negative charged particles, each carries a fiction of an electron's charge.
Such particles responsable for forming nucleus/atom/matter, conducting EM wave, transfer force/energy.
Find a way to detect such particles, you know better ways. Maybe few books in physics could be rewrite.
This type of thinking leads to unscientific theories. A scientist never says "I don't understand this explanation so this other explanation I came up with is better." A scientist instead says "I deeply understand the current mainstream explanation and here are the flaws I have found it and here is my idea to correct them."
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Thank you all deeply for your comments, I am so hunger to learn the mystery of the universe. But in no way I am a scientist, I know too little.
I don't understand QM, the words just make no sence to me. Atoms are compact packed in matters, solar systems are far away seperated. EM force is 10^33 times gravity. Does solar systems share planets? How is chemical bonds obiting?
It just too hard to swollow.
I suggested a new particle to fit the gape and it seems more acceptable to me.
Think about it, if such particles is real, there should be a way to proof it.
I am thinking a high speed fan in vacuum should produce some kind EM field/wind.
Please open your mind, design/find a way to detect enertron - an imaginary negative charged tiny particle that fills space.
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Thank you all deeply for your comments, I am so hunger to learn the mystery of the universe. But in no way I am a scientist, I know too little.
I don't understand QM, the words just make no sence to me. Atoms are compact packed in matters, solar systems are far away seperated. EM force is 10^33 times gravity. Does solar systems share planets? How is chemical bonds obiting?
The nice thing about science is that it doesn't care if you understand it or not. Quantum mechanics works and it explains the phenomena you describe (at least those involving electron orbitals). There is absolutely no reason to introduce a new particle to explain this. More importantly, quantum mechanics not only successfully describes electron orbitals, but it explained many other phenomena that had previously been mysterious (the photoelectric effect, black body radiation, etc.) and predicted new effects that were later tested and verified (wave-particle duality, the Zeeman effect, new particles in the standard model, etc.) If your particle does all that, then congratulations! You've rediscovered quantum mechanics. If it doesn't do all that, then there is no point using it instead of quantum mechanics.
If you want to propose an extension to quantum mechanics, which is a major area of research in physics, you first have to understand it. That takes a lot of work, just as becoming an expert in anything in life takes a lot of work.
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I only want an answer, why positive charge and negative charge in an atom not stick together?
F= p x q/r^2 Two opposite charges should always stick together if nothing separates them.
What is obit, shell, electron cloud? Anything that is negative charged should be automaticly falling into nucleus.
No matter what theory, please help me to understand.
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Photon is a invented word, there is no photon but electromagnetic wave.
First off, as lightarrow indicated, all words are ”invented.”
Which thread are you referring to? I don't remember to have written this (but it's possible, my memory is not as fresh as once...).
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lightarrow
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I only want an answer, why positive charge and negative charge in an atom not stick together?
F= p x q/r^2 Two opposite charges should always stick together if nothing separates them.
What is obit, shell, electron cloud? Anything that is negative charged should be automaticly falling into nucleus.
What you say is not always true. Is true only for classical objects. In particular, it's true for charged particles which can be considered as spatially separated, spatially localized corpuscles. Electrons in the atom are not spatially localized corpuscles.
So, classical theory, which says that electrons should stick to the protons, is meaningless. A new theory is required: quantum mechanics.
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lightarrow
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Atoms are compactly packed in matter, solar systems are far away seperated.
Atoms have most of their mass in a compact object in the center (just like the Solar System).
Atoms can be closely packed together (as in a solid), or widely separated (as in a "noble gas" like neon).
Solar systems can be closely packed together (as in a globular cluster) or widely separated (as in our part of the galactic arm).
The main difference is that in a solar system, masses are large and quantum effects can be ignored.
In contrast, in an atom, the wavelength of the electron is comparable to the size of the atom - you could almost say that the wavelength of the electron defines the size of the atom.
You can demonstrate this by making an atom from a proton and a meson instead of the regular proton and electron - the meson has a much shorter wavelength than an electron, and the resulting "atom" is much smaller than a hydrogen atom. This is not because the meson has a stronger electric charge than the electron - they have equal charges; it is due to the fact that these tiny objects have a quantum nature.
It can't be due to tiny negative charges floating everywhere in space, because this would imply that there are less of them near a meson than an electron.
Does solar systems share planets?
You can imagine closely spaced Suns in a globular cluster where planets first circle one star, then later circle another star.
But the gravitational forces between multiple planets and stars will end up flinging some planets into the star, and others into interstellar space.
This does not happen in atoms because the Pauli Exclusion Principle (among other things) keeps electrons (and mesons) from sharing the same orbits. This does not happen for planets.
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I only want an answer, why positive charge and negative charge in an atom not stick together?
F= p x q/r^2 Two opposite charges should always stick together if nothing separates them.
What is obit, shell, electron cloud? Anything that is negative charged should be automaticly falling into nucleus.
What you say is not always true. Is true only for classical objects. In particular, it's true for charged particles which can be considered as spatially separated, spatially localized corpuscles. Electrons in the atom are not spatially localized corpuscles.
So, classical theory, which says that electrons should stick to the protons, is meaningless. A new theory is required: quantum mechanics.
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lightarrow
Lightarrow is absolutely correct. If you're thinking purely classically, which you are, an electron will inevitably fall into the nucleus. Even if you set it up in an orbit around the nucleus, like the moon around the earth, it would quickly radiate away energy and fall into the nucleus. That would be the end of the story except we obviously observe that electrons do not fall into the nucleus, so this has to be explained. So it becomes a task to find the best model to explain this and the result is quantum mechanics. The reason it is the best model is that it was not chosen solely to explain this. It was formulated to explain both this problem and many other things and it does so amazingly well. It also predicted lots of other effects that were later discovered. It has been so well tested that any model that comes along to improve on quantum mechanics is going to have to include all of its predictions and then add to them. So even if you were to find a theory of a new particle to explain electron orbitals, you'd have to show first that it agreed with quantum mechanics and then what else it explains.
If you want to know the details, you have to be willing to tackle a lot of fairly heavy math. Unfortunately, the quantum world is not like our own, which is why it took so long to discover quantum mechanics. It is extremely difficult to think of quantum phenomena in terms of our daily experiences.
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Thanks for helping me out! JP said it the best!
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Which thread are you referring to? I don't remember to have written this (but it's possible, my memory is not as fresh as once...).
My mistake. I thought it was you but it was actually Bored Chemist. And he didn't actually say it, but sort of implied it. I.e.
perhaps you would like to give us a list of words that are not made up.
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It's becoming increasingly difficult to hide the fact that even the laws that govern our reality are the result of some rather creative design work by someone that really enjoys math.
I borrowed that from another forum. I seriously agreed.
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It's becoming increasingly difficult to hide the fact that even the laws that govern our reality are the result of some rather creative design work by someone that really enjoys math.
Not true. Physicists use math because it’s said to be the language of physics. That means we use math to describe physical laws. There’s no way to describe what’s going on in nature without using math. It let’s us describe exactly what’s going it. It gives us a way to describe the relationship between different physical quantities. This simply cannot be done without math and by definition, it’s the task of physics and the physicist to describe what’s going on in nature.
Go ahead and give it a try. Try to describe the laws of nature without math. Try doing it with the theory of electromagnetism.
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It’s known that light is an electromagnetic wave. It’s also known that many metals emit electrons when light is shined on it. If electromagnetic field theory was correct then the energy from the EM field of the light would transfer energy to the electron which would then be able to over come the work function of the metal and fly off. However that takes time to happen according to EM theory is about 50 years. However its observed to happen nearly instantaneously. That’s how Einstein came up with the theory of photons and why he was awarded the Nobel Prize for it. Einstein spoke of “light quanta” something like that. I never read the original paper. I’ve been unable to find it in English.
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So is EM theory correct?
If photon transfer momentum to electron to knock it off atom, how many photons hit a electron at same time? What is the inpact angle?
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So is EM theory correct?
Of course it’s correct. Within its domain of applicability it’s correct. When you try to apply it to sub atomic physics it fails. However that’s outside its domain of applicability. Just like Newtonian mechanics (aka classical mechanics) is correct within its domain of applicability. When you try to apply classical mechanics to the sub atomic domain it too fails. That’s why quantum mechanics was created. And EM theory not working on the sub atomic domain is why quantum electrodynamics (aka QED) was created.
If photon transfer momentum to electron to knock it off atom, how many photons hit a electron at same time?
One.
What is the inpact angle?
I don’t know what an impact angle is. Please define the term. I think you mixed two terms; impact parameter and scattering angle.
I know what a scattering angle is. Is that what you mean? If so then it can have any value between 0 and 180 degrees. There is a corresponding change in wavelength. There’s no way to predict which value it will be from initial conditions. For example; when a photon strikes one of the inner electrons in, say, a carbon atom there is virtually no shift in wavelength. That’s because the inner electrons are tightly bound to the atom and it’s the whole atom that recoils rather than just the inner electron. Since the mass of the atom is about 10,000 times that of the electron the shift is negligible.
I hope that helps.
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Of cause it helps a lot Pete, I been wondering all my life for those questions. I sincerely appreciate!
I thought particles have mass, charge, shape just like matter. That's why I ask the impact angle of photon and electron.
It is spooky to think how photon is produced, why all kinds of photons have the same speed but different impact momentum?
What's the gun that shooting photons? What's the mechanism? How photon becomes heat? Is it possible more than one photon hit electron within a very short time so give electron higher escaping speed/voltage?
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I thought particles have mass, charge, shape just like matter.
Particles have mass and charge. They don’t have a shape though. However particles like electrons are thought to be point particles which has no dimensions at all.
That's why I ask the impact angle of photon and electron.
But you never told me what you meant by impact angle of photon and electron. As far as I know there is no such thing. As I indicated you have it confused with impact parameter and scattering angle.
It is spooky to think how photon is produced, why all kinds of photons have the same speed but different impact momentum?
They differ by wavelength.
What's the gun that shooting photons?
Atoms emit photons when one of the electrons transitions from a higher state of energy to a lower state. When that happens a photon is emitted.
What's the mechanism?
I don’t think that anybody knows other than what I’ve said.
How photon becomes heat?
When a photon hits an atom some of the energy can go into the kinetic energy of the atom. When the kinetic energy of the atoms that makes up a body increases the temperature increases.
Is it possible more than one photon hit electron within a very short time so give electron higher escaping speed/voltage?
I don’t see why not.
Have you ever thought about buying a book on the subject? Try Quantum Mechanics by A.P. French and Edwin F. Taylor. It’s a great book. It used to be used at MIT to learn quantum mechanics.
How much math do you know? What math do you know? Algebra? Trigonometry? Geometry? Calculus? Etc?
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Haha, I don't know what's the second thing. The rest 3 was like c- in school.
Sweet night Pete, I be thinking long time.
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I thought particles have mass, charge, shape just like matter.
Particles have mass and charge. They don’t have a shape though. However particles like electrons are thought to be point particles which has no dimensions at all.
So particles could have charge, mass and spin but no volume?
That's why I ask the impact angle of photon and electron.
But you never told me what you meant by impact angle of photon and electron. As far as I know there is no such thing. As I indicated you have it confused with impact parameter and scattering angle.
It is spooky to think how photon is produced, why all kinds of photons have the same speed but different impact momentum?
They differ by wavelength.
So photon moves along a sin wave path?
What's the gun that shooting photons?
Atoms emit photons when one of the electrons transitions from a higher state of energy to a lower state. When that happens a photon is emitted.
What is state of energy? How it works?
What's the mechanism?
I don’t think that anybody knows other than what I’ve said.
Don't know the mechanism, how is the theory stands?
How photon becomes heat?
When a photon hits an atom some of the energy can go into the kinetic energy of the atom. When the kinetic energy of the atoms that makes up a body increases the temperature increases.
What is the kinetic energy of the atom? Is it the vibration of the electron bond within atoms?
Is it possible more than one photon hit electron within a very short time so give electron higher escaping speed/voltage?
I don’t see why not.
If so, use same color denser light beam should produce higher voltage, is it true?
Thanks Pete.
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So particles could have charge, mass and spin but no volume?
Yes. That’s correct.
So photon moves along a sin wave path?
Not really, no.
What is state of energy? How it works?
You’d understand it better if I rephrased it since that may not make sense to you given that you’re not a native English speaker. It’s the same as if I phrased it like this
Atoms emit photons when one of the electrons transitions from a quantum state having energy E_m to a quantum state having the energy E_n where E_n < E_m.
Does that make more sense?
Don't know the mechanism, how is the theory stands?
Why shouldn’t it? Theories aren’t always mean to define the mechanism for things in nature. Most of the time they merely describe what’s going on in nature. You don’t seem to understand that part of physics. You seem to think physics is all about knowing all the mechanisms of how nature does what it does. If so then you’re way off.
What is the kinetic energy of the atom?
If the atom of mass m is moving much slower than the speed of light then its kinetic energy is K = mv^2/2
If so, use same color denser light beam should produce higher voltage, is it true?
Why would a laser beam produce any voltage at all? Are you referring to the strength of the field of the light it emits?
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So particles could have charge, mass and spin but no volume?
Yes. That’s correct.
How's that possible? Spin without volume? How do you know it spins? Deriction? Speed? Is point particles real or imaginary?
So photon moves along a sin wave path?
Not really, no.
How's photons moving path? A straight line or what? How a particle moves a wave patten?
What is state of energy? How it works?
You’d understand it better if I rephrased it since that may not make sense to you given that you’re not a native English speaker. It’s the same as if I phrased it like this
Atoms emit photons when one of the electrons transitions from a quantum state having energy E_m to a quantum state having the energy E_n where E_n < E_m.
Does that make more sense?
How atom emit photon? What is electron's quantum state? I understand the rest.
Don't know the mechanism, how is the theory stands?
Why shouldn’t it? Theories aren’t always mean to define the mechanism for things in nature. Most of the time they merely describe what’s going on in nature. You don’t seem to understand that part of physics. You seem to think physics is all about knowing all the mechanisms of how nature does what it does. If so then you’re way off.
I am way off, I thought theory is men describe what he thinks is going on nature.
What is the kinetic energy of the atom?
If the atom of mass m is moving much slower than the speed of light then its kinetic energy is K = mv^2/2
I mean the energy photon transfered to a rest atom, does the impact force make the electron vibrating faster or obiting higher? If photon is particle, it's kinetic energy should be mc^2/2, why E=h x frenquency?
If so, use same color denser light beam should produce higher voltage, is it true?
Why would a laser beam produce any voltage at all? Are you referring to the strength of the field of the light it emits?
I am thinking solar cell in the yard, if we use few mirrors to reflact more sun light on the cell, do we get more current or voltage?
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I am thinking solar cell in the yard, if we use few mirrors to reflact more sun light on the cell, do we get more current or voltage?
More current. When you reflect light from other areas onto a solar cell, all you are doing is pouring more of the same kind of photons onto the photocell. There will be a linear relationship between the amount of light in photons per second and the current the photocell produces. Therefore if N photons per second produces a current of I then 2N photons per second will produce a current of 2I.
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Pete, Thanks. I am thinking, next life I better just study auto repair.
Thanks everyone, all my teachers.
Wish you great weekend!