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Thread: A couple things I have been pondering

  1. #1 A couple things I have been pondering 
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    Hello,
    After pondering the following, I finally felt like looking for other people's opinions. So I began to research them online. When I didn't get my answers, I decided to join a forum to phase my questions the way I needed.
    And yes, I know all of these questions have a long, detailed explanation. I'm going to be straight forward about it: Most of the stuff I find on these things goes over my head. Sorry.

    One:
    I wanted to know if mechanical and electromagnetic waves were the same thing just with different aspects- say speed. So I did some, very little really- online research.

    Here is what I found:
    In the beginning of my search, I was looking up sound and radio waves. I discovered sound waves travel at the speed of, well... sound. Duh you idiot! I also discovered sound is a mechanical wave, requiring matter to pass through.
    I discovered radio waves are electromagnetic waves, supposedly not requiring mass to pass though. I will explain why I say supposedly later. I also discovered that electromagnetic waves travel somewhere around the speeds of light (I found differing lights have differing speeds).

    So I tried to find why the two types of waves need/do not need matter. Of course half the answers went over my head. I think I understood the mechanical. If I understand correctly, mechanical waves are created via pressure that passes through matter in the form of energy, coming back out as pressure. If correct, understood. So then how do electromagnetic waves work?

    Now I said I would explain what I meant by supposedly above.
    As I understand, not even space is a true vacuum, which means there is a minuscule, perhaps infinitesimal amount of matter- right?
    Is it possible that electromagnetic waves do need matter- just not nearly as much as mechanical?
    Also, if electromagnetic waves don't need any matter at all, wouldn't they also be able to completely ignore matter? Radio waves are affected by walls, buildings, trees, water, etc. Light cannot go through non-transparent solid objects, which I know is explained via emission, absorption, transmission, and reflection/scattering, but what causes these?

    Two:
    As I understand it, matter is, also at it's very base, nothing but energy, governed by stability (Atom bombs manipulate this, right?). So if the energy can be released in such a violent/destructive fashion, wouldn't it also be possible to gather up energy and create an object- or at the very least matter? And how do waves fit into this? Wouldn't they be able to manipulate the very reality we live in- limited by the waves' individual rules?

    Three:
    Plasma. What is it? As far as I understand, plasma is like super-fire right? No material can survive it. But does plasma consume the material and energy it destroys, like fire?

    Four:
    What about Tesla's cold electricity? Is it a thing and why does it seem to be ignored?

    I apologize in advance if these things have obvious answers and I just failed to find or understand them.
    Thanks!


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  3. #2  
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    Quote Originally Posted by Yonathan Yeager View Post
    Hello,
    After pondering the following, I finally felt like looking for other people's opinions. So I began to research them online. When I didn't get my answers, I decided to join a forum to phase my questions the way I needed.
    And yes, I know all of these questions have a long, detailed explanation. I'm going to be straight forward about it: Most of the stuff I find on these things goes over my head. Sorry.

    One:
    I wanted to know if mechanical and electromagnetic waves were the same thing just with different aspects- say speed. So I did some, very little really- online research.

    Here is what I found:
    In the beginning of my search, I was looking up sound and radio waves. I discovered sound waves travel at the speed of, well... sound. Duh you idiot! I also discovered sound is a mechanical wave, requiring matter to pass through.
    I discovered radio waves are electromagnetic waves, supposedly not requiring mass to pass though. I will explain why I say supposedly later. I also discovered that electromagnetic waves travel somewhere around the speeds of light (I found differing lights have differing speeds).

    So I tried to find why the two types of waves need/do not need matter. Of course half the answers went over my head. I think I understood the mechanical. If I understand correctly, mechanical waves are created via pressure that passes through matter in the form of energy, coming back out as pressure. If correct, understood. So then how do electromagnetic waves work?

    Now I said I would explain what I meant by supposedly above.
    As I understand, not even space is a true vacuum, which means there is a minuscule, perhaps infinitesimal amount of matter- right?
    Is it possible that electromagnetic waves do need matter- just not nearly as much as mechanical?
    Also, if electromagnetic waves don't need any matter at all, wouldn't they also be able to completely ignore matter? Radio waves are affected by walls, buildings, trees, water, etc. Light cannot go through non-transparent solid objects, which I know is explained via emission, absorption, transmission, and reflection/scattering, but what causes these?

    Two:
    As I understand it, matter is, also at it's very base, nothing but energy, governed by stability (Atom bombs manipulate this, right?). So if the energy can be released in such a violent/destructive fashion, wouldn't it also be possible to gather up energy and create an object- or at the very least matter? And how do waves fit into this? Wouldn't they be able to manipulate the very reality we live in- limited by the waves' individual rules?

    Three:
    Plasma. What is it? As far as I understand, plasma is like super-fire right? No material can survive it. But does plasma consume the material and energy it destroys, like fire?

    Four:
    What about Tesla's cold electricity? Is it a thing and why does it seem to be ignored?

    I apologize in advance if these things have obvious answers and I just failed to find or understand them.
    Thanks!
    There are (occasionally) proper physicists here that may be able to do a better job but, just to get started, EM waves indeed do not need a material medium. They are oscillating electric and magnetic fields. A field can exist in space without any matter.

    The reason why objects affect EM waves (refraction etc) is that they contain electric charges (electrons) that move in response to an oscillating electric field, an effect called polarisation. As they do so they alternately borrow energy from the field and then give it back. This affects the passage of the wave when it encounters objects, which leads to refraction, reflection etc.

    Please do not think of matter as "nothing but energy". It is a common misconception to think of energy as "stuff". It isn't. That's Star Trek but not physics. Energy is just a property of a physical system, like mass, or momentum.

    Matter "has" energy, just as it "has" mass. But it we can't say it "is" energy, any more than we can say a moving cricket ball "is" momentum.

    A physical system does not need to involve matter. It can consist of just fields, as in the case of EM radiation. EM radiation has no mass but it does have energy, momentum, polarisation, speed, frequency etc. All these, including energy, are properties of the radiation.

    Plasma is a state of matter in which electrons have been knocked out of the atoms, leaving +ve ions behind, so that you have a sort of gas but made up of positive ions and electrons, rather than the neutral atoms or molecules that you have in a normal gas.

    I had never heard of cold electricity until now, and the mention of Tesla makes me suspicious. This is because Tesla, who went mad towards the end of his life, is beloved by cranks and free energy charlatans. When I google "cold electricity" I get a lot of rubbish about aether etc - crank territory, in fact. So I suspect it may be a myth, or a name given to something else by people trying to sell you a machine that doesn't work, or something like that. If you can provide more details of where you have come across it, perhaps I can make a more helpful comment.

    P.S. It has been known for cranks to come to forums like this, posing as innocents but then, after a few exchanges, running up the Jolly Roger and coming out with the crank agenda they really want to sound off about. Naturally I hope you won't turn out to be one of those, but Tesla for me is a bit of a danger sign. So I'm looking forward to a reassuring response.


    Last edited by exchemist; November 19th, 2020 at 06:14 AM.
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    Thanks for a quick reply. I must say I have never been answered so quickly on a forum before.

    You have somewhat explained electromagnetic waves, but now my question is: Are waves fields, or do waves require fields to pass through, or is it the opposite- fields repel waves?
    I am assuming it is not the last one, as opposite waves cancel each other out- so to "repel" a wave isn't really possible is it?

    From what I understand, atoms are made up of electrons and quarks. Quarks are, from what I have read, fast moving points of energy. Does this mean that electrons are the base of matter?

    So plasma is a bunch of positive ions... surrounded by the electrons I guess? What happens to the electrons once they are knocked out of the atom?

    I understand the hesitation behind the Tesla topic. I'm simply one to try and learn for myself before writing something off, and I just couldn't find much on "cold electricity", the same way you couldn't. If Tesla is a sore spot, I won't touch.
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    Quote Originally Posted by Yonathan Yeager View Post
    Thanks for a quick reply. I must say I have never been answered so quickly on a forum before.

    You have somewhat explained electromagnetic waves, but now my question is: Are waves fields, or do waves require fields to pass through, or is it the opposite- fields repel waves?
    I am assuming it is not the last one, as opposite waves cancel each other out- so to "repel" a wave isn't really possible is it?

    From what I understand, atoms are made up of electrons and quarks. Quarks are, from what I have read, fast moving points of energy. Does this mean that electrons are the base of matter?

    So plasma is a bunch of positive ions... surrounded by the electrons I guess? What happens to the electrons once they are knocked out of the atom?

    I understand the hesitation behind the Tesla topic. I'm simply one to try and learn for myself before writing something off, and I just couldn't find much on "cold electricity", the same way you couldn't. If Tesla is a sore spot, I won't touch.
    Haha, thanks for the reply. Tesla isn't a sore spot, but a lot of us have got burnt wasting our time on cranks, among whom Tesla seems to be a favourite, for some reason. So I'm a bit wary when Tesla is brought up, that's all.

    For many purposes, EM radiation can be thought of as comprising waves in the electric and magnetic fields*. That is the classical (c.19th, Maxwell) view of them. This got modified by Einstein and others in the c.20th, when it was realised that the radiation is quantised. Hence we now regard it as coming in discrete bits called photons, while at the same time having wave properties. (This is part of the wave/particle duality that runs through all of quantum theory - a big subject.)

    You certainly get constructive and destructive interference involving light - it is how diffraction patterns are produced - but you are right that light can't repel light.

    Your comment on matter is a bit off-target. Quarks (which, yes, are believed to be the constituents of the protons and neutrons that make up the nucleus of atoms) are not "fast-moving points of energy". As I said in the previous post, you can't have something made of energy. Energy is just a property of something, not an entity in its own right. A quark is a quark and it has energy and mass, along with electric charge , spin and other properties.

    Atoms are made up of positively charged nuclei (made of protons and neutrons) and negatively charged electrons circulating round them, bound to them by electrostatic attraction. Almost all the mass of an atom is in the nucleus, but the size of the atom is determined by the space the cloud of electrons occupies. (This was very surprising to Ernest Rutherford, when Geiger and Marsden discovered it in their famous experiment in 1909: https://www.bbc.co.uk/bitesize/guide...4qt/revision/1 )

    If you give an electron more energy, it jumps to a higher energy state, in which it is on average further away from the nucleus. If you give it enough, it exceeds "escape velocity" and flies away from the nucleus entirely At that point you have ionised the atom. In a plasma, some of the electrons have enough energy to have been ionised in this way. So a plasma consists of a mixture of ions and electrons.https://en.wikipedia.org/wiki/Plasma_%28physics%29


    * A wave is a periodic, travelling disturbance in something. Water waves are a disturbance in the water level. Sound waves are a disturbance in the pressure level. EM waves are a disturbance in the level (value) of the electric field and the magnetic field.
    Last edited by exchemist; November 19th, 2020 at 01:26 PM.
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    "Your comment on matter is a bit off-target. Quarks (which, yes, are believed to be the constituents of the protons and neutrons that make up the nucleus of atoms) are not "fast-moving points of energy". As I said in the previous post, you can't have something made of energy. Energy is just a property of something, not an entity in its own right. A quark is a quark and it has energy and mass, along with electric charge , spin and other properties."

    Well then. I think that's the last time I'll trust google to give me accurate information. smh.

    So you said the size of the atom is determined by the space of the "cloud" that the electrons occupy. Does this mean that "clouds" simply add to the size of the nuclei, or that the size of the nuclei is relevant to the "cloud"? I would assume the former, but I have been surprised a few times already.

    After the electrons have been knocked "out of alignment" so to speak, how do the nuclei and electrons now respond to things like wind?
    Also, I was under the belief that anything with atoms can become plasma. True or false?
    Secondly, I would assume that when you add atoms to already existing plasma, the electrons' extra energy would become spread more thin- would the electrons then be pulled back to nuclei, or once out of alignment, they need an external force to put them back together?

    And yes, I was wondering about the water waves. I came across them when looking up waves. I am assuming they require simply liquid - or must it be water?
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    Quote Originally Posted by Yonathan Yeager View Post
    "Your comment on matter is a bit off-target. Quarks (which, yes, are believed to be the constituents of the protons and neutrons that make up the nucleus of atoms) are not "fast-moving points of energy". As I said in the previous post, you can't have something made of energy. Energy is just a property of something, not an entity in its own right. A quark is a quark and it has energy and mass, along with electric charge , spin and other properties."

    Well then. I think that's the last time I'll trust google to give me accurate information. smh.

    So you said the size of the atom is determined by the space of the "cloud" that the electrons occupy. Does this mean that "clouds" simply add to the size of the nuclei, or that the size of the nuclei is relevant to the "cloud"? I would assume the former, but I have been surprised a few times already.

    After the electrons have been knocked "out of alignment" so to speak, how do the nuclei and electrons now respond to things like wind?
    Also, I was under the belief that anything with atoms can become plasma. True or false?
    Secondly, I would assume that when you add atoms to already existing plasma, the electrons' extra energy would become spread more thin- would the electrons then be pulled back to nuclei, or once out of alignment, they need an external force to put them back together?

    And yes, I was wondering about the water waves. I came across them when looking up waves. I am assuming they require simply liquid - or must it be water?
    The size of an atom is essentially determined by what stops another one from getting any closer. When the two "touch", one starts to repel the other so that further approach requires them to be "squashed". For a pair of approaching atoms, it is their respective electron clouds that encounter one another first, causing mutual repulsion.

    The size of the nucleus is not relevant: it is many orders of magnitude smaller than the dimensions of the electron cloud. An atomic nucleus is only ~1/10,000th the size of the electron cloud surrounding it. Yet the nucleus contains 99.9% of the mass of the atom. This is what people mean by atoms being mostly empty space, which you sometimes see written.

    Anything with atoms can become plasma, because any atom can be ionised. But you are right that the electrons will tend to drop back into the ions and make neutral atoms once more, if they don't have enough energy to stay ionised. (The ions are +ve and the electrons are -ve so they are attracted together.) To sustain a plasma, you either need it to be so hot that thermal motion of the atoms is violent enough to keep knocking electrons out of the atoms, or you need some other way to keep the ionisation going, e.g. via an electrical discharge, as in a mercury lamp. You also can have a devil of a job to contain a plasma. If it touches the cool walls of a container it will lose energy and stop being a plasma - unless you keep pumping it up with a discharge. (The sun is largely a thermal plasma of hydrogen, contained by the force of its own gravity).

    With waves, all you need is some extended medium that resists displacement from an equilibrium position. With the surface of water, it is gravity that makes it want to return to a set level. So if you displace the surface at one point, e.g by throwing a stone into a pond, it rebounds and overshoots, producing an alternate rising and falling, which then travels outward. Any liquid under gravity will do the same. In the case of sound, you suddenly move a surface (e.g loudspeaker cone), compressing the air a bit on one side and expanding it a bit on the other. The air resists the compression and expansion, rebounds and overshoots, and this causes an alternate compression and expansion pattern that travels outwards. (This is also what happens to the ground in earthquakes, by the way.) With a radio wave, you move the electrons up and down a wire (AC) in the transmitter, causing an alternating +ve and -ve electric field. This tries to return to its ambient value of zero, rebounds and overshoots and the electrical disturbance travels outwards (accompanied in this case by a magnetic wave as well, because whenever an electric charge moves, it creates a magnetic field.)

    Waves on the surface of a liquid, and electromagnetic waves, are examples of "transverse" waves, because the displacement of the medium is at right angles to the direction in which the wave travels. Sound waves and other pressure waves are examples of "longitudinal" waves, because with them the displacement is in the same direction as the direction the wave travels.
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    Quote Originally Posted by Yonathan Yeager View Post

    So you said the size of the atom is determined by the space of the "cloud" that the electrons occupy. Does this mean that "clouds" simply add to the size of the nuclei, or that the size of the nuclei is relevant to the "cloud"? I would assume the former, but I have been surprised a few times already.
    It's the later. While size of the nuclei do vary from element to element, this is due to the fact that they have to contain the same number of protons as there are electrons (for an non-ionized atom), plus any Neutrons needed to help hold the nucleus together.*
    Nuclei range from 1.7e-15m to to more than ten times that size.
    Atoms (due to the size of the electron cloud) are some 100,000 times larger than their nuclei. So the nuclei are small, compact structures in the middle of a much, much larger cloud of electrons surrounding it.


    * technically, it is the number of protons that determines the element. This in turn determines the number of electrons. And it is the number and arrangement of the electrons that determine physical and chemical properties of the element.
    "Men are apt to mistake the strength of their feelings for the strength of their argument.
    The heated mind resents the chill touch & relentless scrutiny of logic"-W.E. Gladstone


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    Quote Originally Posted by Yonathan Yeager View Post
    So you said the size of the atom is determined by the space of the "cloud" that the electrons occupy. Does this mean that "clouds" simply add to the size of the nuclei, or that the size of the nuclei is relevant to the "cloud"? I would assume the former, but I have been surprised a few times already.

    After the electrons have been knocked "out of alignment" so to speak, how do the nuclei and electrons now respond to things like wind?
    Also, I was under the belief that anything with atoms can become plasma. True or false?
    Secondly, I would assume that when you add atoms to already existing plasma, the electrons' extra energy would become spread more thin- would the electrons then be pulled back to nuclei, or once out of alignment, they need an external force to put them back together?

    And yes, I was wondering about the water waves. I came across them when looking up waves. I am assuming they require simply liquid - or must it be water?
    A wonderful book you might find enlightening is "The Story of Atomic Energy" by Laura Fermi (wife of physics Nobelist Enrico Fermi). It's out of print, but many libraries have it. There may be online ebooks as well, but I haven't looked.

    She describes very well how we went from "Do atoms exist?" to "We can get staggering amounts of energy from atoms" in just a few decades.

    A more recent, and much more comprehensive, treatment is "The Making of the Atomic Bomb" by Richard Rhodes. It's one of the very few books written by a non-scientist that did not make me groan in agony over botched explanations of the science. And even though we know how the story ends, he tells the story in a way that maintains suspense. Rhodes richly deserved the Pulitzer for this book.
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    To exchemist's (always) excellent replies, I would add only a few comments.

    Quote Originally Posted by Yonathan Yeager View Post
    I discovered radio waves are electromagnetic waves, supposedly not requiring mass to pass though. I will explain why I say supposedly later.
    Oh dear. Light travels so well in a vacuum that a practical vacuum is filled with electromagnetic energy. No matter to be found. More on this shortly.

    I also discovered that electromagnetic waves travel somewhere around the speeds of light (I found differing lights have differing speeds).
    In a vacuum light travels at c. If by "differing lights" you mean "light of different wavelengths (colors)", you "found" something quite wrong, for it matters not what color it is. Light travels at c in a vacuum (I'm repeating myself deliberately). I don't know where you got the wrong information that light travels at different speeds (it can if traveling through matter -- which is why we have rainbows -- but I'm talking strictly about a vacuum), but you need to look elsewhere. Wikipedia is actually a reasonably reliable source; I suggest you start there. You seem to be finding "information" written by idiots or cranks (the two groups overlap greatly).

    Now I said I would explain what I meant by supposedly above.
    As I understand, not even space is a true vacuum, which means there is a minuscule, perhaps infinitesimal amount of matter- right?
    Your conclusion does not follow logically from the premise, so it fails on that basis. You have neglected a possibly infinite number of non-mass things that could be in an imperfect vacuum.

    Is it possible that electromagnetic waves do need matter- just not nearly as much as mechanical?
    Also, if electromagnetic waves don't need any matter at all, wouldn't they also be able to completely ignore matter?
    Again, your conclusion does not follow logically from your premise at all. Not needing something does not mean that it can't interact with that something. I don't need a Lamborghini (despite what I try to convince my wife), but I can certainly interact with one.

    Luxury sports cars aside, we know experimentally that as you operate a vacuum pump to exhaust, say, a bell jar, the transmission of light does not change (actually, it gets a tiny bit better, because air is imperfectly transparent, but let us neglect that tiny effect which, in any case, contradicts your conclusion). If your conclusion were correct, wouldn't one expect to see the transmission of light degrade as one removes the matter that you say is needed to support light? We do not observe such an effect at all.

    One of the harder things is to develop a rigorous respect for logic. Be your own harshest critic. Spend some effort to see if you can find a counterexample that disconfirms your conclusions. As you exercise that habit more and more, you'll find that you will understand more, and at an increasing rate, because you'll spend less time pondering a false conundrum. Real conundrums should suffice!
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    In reply to exchemist:
    Well then. I think that answers most of my original questions. Tbh, thanks for being patient and fixing up my misconceptions.


    In reply to Janus:
    Thank you for that explanation. That does however bring up a question/s about the "cloud".
    Is the cloud a magnetic field? I am assuming it is, given the negative(electrons) and positives(protons) of the atom. Is the cloud itself or the electrons responsible for repelling the other atoms?


    In reply to tk421:
    I am currently downloading "The making of the atomic bomb".

    "Oh dear. Light travels so well in a vacuum that a practical vacuum is filled with electromagnetic energy. No matter to be found. More on this shortly."

    My confusion lied in that a vacuum cannot even include non-matter things- which you cleared up with:
    "You have neglected a possibly infinite number of non-mass things that could be in an imperfect vacuum."
    So now though I wonder: What would happen if a true vacuum came into existence?

    Also, the "light at different speeds" I had read long ago. It was kind of like a bit of weird but interesting information that I had picked up, but time diminished the context. Yes, it had to do with light passing through mediums, now that you say that.
    And yes, I was, apparently, coming across false info repeatedly. I would have really looked into wikipedia, but every time I begin reading things like physics, most of it goes over my head, leaving me frustrated.



    My last question for this comment:
    Would it be theoretically possible to manipulate the amount of protons, electrons, and neurons- to make a different atom? Say, nickel to copper? I understand that that kind of thing is far fetched, probably impossible, and probably considered pseudo-science. But if the make up of an element is based on the amount of protons, electrons, and neurons in an atom, and if you could manipulate that amount, wouldn't it be possible to change one element to another?
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    Quote Originally Posted by Yonathan Yeager View Post
    In reply to exchemist:
    Well then. I think that answers most of my original questions. Tbh, thanks for being patient and fixing up my misconceptions.


    In reply to Janus:
    Thank you for that explanation. That does however bring up a question/s about the "cloud".
    Is the cloud a magnetic field? I am assuming it is, given the negative(electrons) and positives(protons) of the atom. Is the cloud itself or the electrons responsible for repelling the other atoms?


    In reply to tk421:
    I am currently downloading "The making of the atomic bomb".

    "Oh dear. Light travels so well in a vacuum that a practical vacuum is filled with electromagnetic energy. No matter to be found. More on this shortly."

    My confusion lied in that a vacuum cannot even include non-matter things- which you cleared up with:
    "You have neglected a possibly infinite number of non-mass things that could be in an imperfect vacuum."
    So now though I wonder: What would happen if a true vacuum came into existence?

    Also, the "light at different speeds" I had read long ago. It was kind of like a bit of weird but interesting information that I had picked up, but time diminished the context. Yes, it had to do with light passing through mediums, now that you say that.
    And yes, I was, apparently, coming across false info repeatedly. I would have really looked into wikipedia, but every time I begin reading things like physics, most of it goes over my head, leaving me frustrated.



    My last question for this comment:
    Would it be theoretically possible to manipulate the amount of protons, electrons, and neurons- to make a different atom? Say, nickel to copper? I understand that that kind of thing is far fetched, probably impossible, and probably considered pseudo-science. But if the make up of an element is based on the amount of protons, electrons, and neurons in an atom, and if you could manipulate that amount, wouldn't it be possible to change one element to another?
    On your last point, there are radioisotopes of Ni that decay to Cu by β-decay, that is, by emission of an electron from the nucleus, thereby turning a neutron into a proton. That gives the nucleus one more +ve charge and so it becomes a Cu atom instead of an Ni atom.

    But that is a natural process. I am not aware of any means by which we can artificially stimulate such changes.

    The thing about light at different speeds sounds to me as if it may be a garbled recollection of how refraction in glass (which splits white light into the colours of the rainbow) is explained. So let me have a go at that while we're about it:-

    When light enters a material medium like water or glass, which is polarisable due to the electrons it contains (see my post 2 in this thread), the "coupling" that takes place between the varying electric field of the light and the electrons in the medium, which are made to move in sympathy, can slow down what is called the "phase velocity" of the light. If a beam of light strikes such a medium obliquely, the side that enters it first will be slowed before the side that enters last and so the beam will be bent through an angle at the point of entry. That is refraction.

    Furthermore, with glass or water, the amount the phase velocity is slowed - and thus the degree to which the light is bent - is greater for higher frequency (shorter wavelength) light than for lower frequency (longer wavelength) light. This effect, which is called "dispersion", causes white light to separate into the colours of the rainbow. (Blue is shorter wavelength than red and the other colours are in between).
    Last edited by exchemist; November 21st, 2020 at 12:21 PM.
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    Quote Originally Posted by Yonathan Yeager View Post
    In reply to exchemist:
    Well then. I think that answers most of my original questions. Tbh, thanks for being patient and fixing up my misconceptions.


    In reply to Janus:
    Thank you for that explanation. That does however bring up a question/s about the "cloud".
    Is the cloud a magnetic field? I am assuming it is, given the negative(electrons) and positives(protons) of the atom. Is the cloud itself or the electrons responsible for repelling the other atoms?

    the "cloud" made up of the individual electrons. Since each electron has a electric charge, each electron contributes to the electric field. So it is the electric field of the electrons that cause atomic repulsion. However, it is a bit more complex than just that. The "cloud" has a type of "structure" to it, which we describe as "shells" each shell has a particular number of electrons it can hold before it is full. "Inner" shells fill up first. The outermost shell, depending on the element, may be full, or more likely, will not be full. Now it turns out that atoms, if they can. tend to fill the outer shell. When it doesn't have enough electrons to do so on its own, it will try and "Share" outer shell electrons with another atom (or more). This "sharing" of electrons allows all the atoms involved to "fill" their outer shell. This what results in chemical bonds which form molecules like H2O (water)


    My last question for this comment:
    Would it be theoretically possible to manipulate the amount of protons, electrons, and neurons- to make a different atom? Say, nickel to copper? I understand that that kind of thing is far fetched, probably impossible, and probably considered pseudo-science. But if the make up of an element is based on the amount of protons, electrons, and neurons in an atom, and if you could manipulate that amount, wouldn't it be possible to change one element to another?
    You are asking about transmutation of elements. Some elements already do this naturally. It is called nuclear decay. It happens when the nucleus of an atom isn't fully stable, which becomes more likely as the number of protons in the nucleus increases. For example Uranium 238 (92 protons, 146 neutrons) decays by ejecting 2 protons and 2 neutrons to become Thorium 234 (90 protons, 144 neutrons). Thorium 234 is not stable either, so it will also decay, but by a different means. It ejects an electron( from the nucleus, not the electron cloud), by converting a neutral neutron into a proton this turns it into Protoactinium 234 ( 91 protons 143 neutrons), Which in turn decays by the same mechanism to become uranium 234 (92 protons, 142 neutrons.
    This continues for many more steps ( called a decay series) until finally lead 206 (which is stable) is reached.

    There is also nuclear fission, where an nucleus can "break apart" into smaller pieces forming lighter elements. This releases a great deal of energy* and is the basis behind the A-bomb, and present day nuclear reactors.

    Fusion can occur when when two atoms of the same element "fuse" together and form a heavy element. This also can release great deal of energy*, and is what fuels our Sun and H-bombs. Fusion works best with light elements. However, it requires some severe conditions to force the nuclei together close enough to fuse. (H-bombs have to use a fission bomb "trigger" to create this)

    We have also been able to artificially make elements that don't naturally occur on the Earth** (24 to this date). This is done either in nuclear reactors or particle accelerators. This takes a lot of energy.

    Now, while it also would be theoretically possible to transmute nickel to copper, doing so would take so much effort and energy that it wouldn't be practical. The end result would not be worth it.



    *Fission and fusion work in the opposite direction, one making lighter elements from heavy and the other heavier elements from lighter, and while this can release energy, this is not always the case. Basically, you can fuse light elements up to Iron and get a net energy output, but t take a net input to fuse elements higher than that. Conversely, you can get a net energy from fissioning heavy elements, but only down to Iron, It takes a net input to fission elements lighter than Iron.

    ** it's not that this elements can't occur in nature, it is just that they are so unstable they don't last long once formed.
    Last edited by Janus; November 24th, 2020 at 12:27 PM.
    "Men are apt to mistake the strength of their feelings for the strength of their argument.
    The heated mind resents the chill touch & relentless scrutiny of logic"-W.E. Gladstone


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  14. #13  
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    Sorry for the late reply.

    Alrighty, that's everything for now.

    Thank you all for spending the time to help me out- I don't think I would have been able to read up on these topics and been able to learn what I did here. For one, I kept coming across false info, and second the probably more accurate things would've went over my head.

    If I ever need something else explained(or I need corrected), this'll be the first place I'll ask- (aside from what I will be able to understand on wikipedia).
    Thanks once again.
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  15. #14  
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    Quote Originally Posted by Yonathan Yeager View Post
    Sorry for the late reply.

    Alrighty, that's everything for now.

    Thank you all for spending the time to help me out- I don't think I would have been able to read up on these topics and been able to learn what I did here. For one, I kept coming across false info, and second the probably more accurate things would've went over my head.

    If I ever need something else explained(or I need corrected), this'll be the first place I'll ask- (aside from what I will be able to understand on wikipedia).
    Thanks once again.
    OK, hope it was useful and see you around.
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