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    victor1985


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    Post  victor1985 Sat Feb 28, 2015 10:47 am

    Hy. I search for books in pdf format or articles or whatever about tactics strategyes and how function weapons and equipment. I know usually nobody gives important informations but sometimes books or articles are made for general knowing of informations. In those books the scientific bases upon the weapons works are written. This kind of books i search.
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    Post  flamming_python Sat Feb 28, 2015 2:30 pm

    victor1985 wrote:I wanna ask something: a ampere is a 6,241x 10^18 electrons that are moving throught circuit. Question is: those electrons where are they after moving? And a coulomb is stationary electrons..... where they stay in a battery and in a electric circuit togheter and separate?

    They all move 'round a circuit. 'Round and 'round they go. So eventually, after some time, you'll see the same electron passing the same point in the circuit as did before.

    Coulomb is equivalent to 6,241x 10^18 electrons, they can be stationary or moving, but I suppose it only really makes sense to talk about coulombs when they are moving - as when they are stationary the circuit is not charged at all and no electricity flows.

    As for where the electrons stay - on the outer shell of the atoms of the conductor. That's where they are at rest. When you apply a voltage, they start hoping from one atom to the next - all in the same direction, and this is what electricity is.
    The larger the conductor you connect to the battery (i.e. a longer wire), the more electrons in total would be moving.
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    Post  victor1985 Sat Feb 28, 2015 3:09 pm

    As far as i know coulomb is the unit measurement for electric charge. Which i do understand as being static atoms (pozitive or negative). The intensity is measured in amphere and is the electrons that pass by a conductor in a second. What do i dont understand well is the difference between electric charge and intensity. Point is i dont understand STATIC ELECTRICITY at all. Better i understand electric circuit.
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    Post  victor1985 Sat Feb 28, 2015 3:15 pm

    More clearly i do understand the coulomb being the static electrons wich are POTEBTUALLY moving and become electric curent. Is like a capacity of body but not yet functionally. Is like saing: if i thrown a rock whit 10 metter/second i can obtain a kinetic energy of x, but i have not yet thrown the rock, but the rock has the potentually force to do it.
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    Post  victor1985 Sat Feb 28, 2015 3:18 pm

    flamming_python wrote:
    victor1985 wrote:I wanna ask something: a ampere is a 6,241x 10^18 electrons that are moving throught circuit. Question is: those electrons where are they after moving? And a coulomb is stationary electrons..... where they stay in a battery and in a electric circuit togheter and separate?

    They all move 'round a circuit. 'Round and 'round they go. So eventually, after some time, you'll see the same electron passing the same point in the circuit as did before.

    Coulomb is equivalent to 6,241x 10^18 electrons, they can be stationary or moving, but I suppose it only really makes sense to talk about coulombs when they are moving - as when they are stationary the circuit is not charged at all and no electricity flows.

    As for where the electrons stay - on the outer shell of the atoms of the conductor. That's where they are at rest. When you apply a voltage, they start hoping from one atom to the next - all in the same direction, and this is what electricity is.
    The larger the conductor you connect to the battery (i.e. a longer wire), the more electrons in total would be moving.

    so a battery what makes whit that plates inside if the curent is given by the electrons in the wire? What is their role? To create the electric field that push the electrons?
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    Post  flamming_python Sat Feb 28, 2015 5:02 pm

    victor1985 wrote:
    flamming_python wrote:
    victor1985 wrote:I wanna ask something: a ampere is a 6,241x 10^18 electrons that are moving throught circuit. Question is: those electrons where are they after moving? And a coulomb is stationary electrons..... where they stay in a battery and in a electric circuit togheter and separate?

    They all move 'round a circuit. 'Round and 'round they go. So eventually, after some time, you'll see the same electron passing the same point in the circuit as did before.

    Coulomb is equivalent to 6,241x 10^18 electrons, they can be stationary or moving, but I suppose it only really makes sense to talk about coulombs when they are moving - as when they are stationary the circuit is not charged at all and no electricity flows.

    As for where the electrons stay - on the outer shell of the atoms of the conductor. That's where they are at rest. When you apply a voltage, they start hoping from one atom to the next - all in the same direction, and this is what electricity is.
    The larger the conductor you connect to the battery (i.e. a longer wire), the more electrons in total would be moving.

    so a battery  what makes whit that plates inside if the curent is given by the electrons in the wire? What is their role? To create the electric field that push the electrons?

    Yes, exactly that. The battery's chemical reactions create a difference between its two terminals, one ends up being more negative (more electrons), the other more positive (less electrons).
    When you connect a wire to the two terminals, the electrons in the wire will be attracted towards the positive terminal and will move towards there, giving you a current.

    victor1985 wrote:More clearly i do understand the coulomb  being the static electrons wich are POTEBTUALLY moving and become electric curent. Is like a capacity of body but not yet functionally. Is like saing: if i thrown a rock whit 10 metter/second i can obtain a kinetic energy of x, but i have not yet thrown the rock, but the rock has the potentually force to do it.

    Electrons always have the same charge, it doesn't matter if they're moving or not.

    Coulomb is just a unit of measurement - it's literally just equivalent to the negative/positive charge of 6,241x 10^18 electrons/protons.

    But at the same time, it doesn't really make sense to speak of coulombs it unless a current is flowing. You don't really use this term to talk about anything other than electricity (i.e. moving current). When electrons aren't moving, and there is no electricity - the electrons still have charge, but the conductor itself is not charged - as the electrons are fixed in orbit around atoms, which are neutral, and the end result is that the entire material is neutral and has no charge.

    If you want to talk about electrons in isolation (like when they are moving through space at close to light speeds), then you use the unit electronvolt to talk about their energy level - which is a slightly different concept but related to that of coulombs and charge.

    victor1985 wrote:As far as i know coulomb is the unit measurement for electric charge. Which i do understand as being static atoms (pozitive or negative). The intensity is measured in amphere and is the electrons that pass by a conductor in a second. What do i dont understand well is the difference between electric charge and intensity. Point is i dont understand STATIC ELECTRICITY at all. Better i understand electric circuit.

    Static electricity is just what happens when you have two locations seperated by an insulator, that have different levels of electric charge. So exactly like how a battery works.

    The electrons balance themselves out by transfering from where there are more of them to where there are less of them. If the difference between the charges of the two places is great enough, the voltage (electromotive force) can be high enough to cause an ionization of the air between these two places (if air is what seperates them), thus temporarily making air into a conductor, with the electrons leaping across it in the form of a spark or electric arc.

    Of course, as soon as the balance is restored and both locations have the same charge - they are electrically neutral and no more current flows. In the absense of a chemical reaction that keeps creating such a difference (i.e. like the one in a battery), there will be no more sparks or electric arcs after the initial one. It happens momentarily and that's it.

    Usually the way such a difference is caused, is by rubbing some surfaces onto certain materials.
    Doing so can rub some electrons off the surface, and thus cause it to be positively charged. As soon as that material touches something else, especially a conductor - the spark happens.
    It can happen to human skin too, which is why humans sometimes get zapped by static.
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    Post  victor1985 Sun Mar 01, 2015 10:05 am

    So when you friction a material upon a material and is created static electricity what exacly happens? Friction make an magnetic field that push the electrons trought air to the other material?
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    Post  victor1985 Sun Mar 01, 2015 10:09 am

    Lets say you friction two objects. In object number one the electrons are travel first inside object number one ; this creates a electric charge and the electrons start jumping in the air to object number two?
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    Post  victor1985 Sun Mar 01, 2015 1:41 pm

    I finded how they make invisible airplanes. Basically the materials that are not conducting electricity and are isolators do not echo the electromagnetic wave of radar. Point is that is not such thing as a perfect isolator so a radar wave is less but anyway reflected. Just you must make more sensitive eauipment to catch even the small amount of waves reflected.
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    Post  victor1985 Sun Mar 01, 2015 2:05 pm

    I finded a material about radar and learn about PRF and PRT. Seems that single antenna wich emit and receive are problematic because of ambigusity. Mean about the wrong locate made when a second echo is emited after first echo is returning. I will learn about separate emitter and receiver of radar. Also modifying speed of wavelenght would help but dunno if is possible. Or alternate wavelenghts or power.
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    Post  flamming_python Sun Mar 01, 2015 8:01 pm

    victor1985 wrote:So when you friction a material upon a material and is created static electricity what exacly happens? Friction make an magnetic field that push the electrons trought air to the other material?

    Friction rubs the electrons off one material onto another. Actually it's not really friction, it's just that when you rub two materials together, the atoms/molecules of one material attract electrons more strongly than the other material's atoms/molecules; this property is called electron affinity. So what happens in the end, is that one material steals electrons from the other.

    The material that has been stolen electrons from, ends up positively charged, with a deficit of electrons. When it touches something else later, electricity conducts through the air from the other material onto it; you see this in the form of sparks.
    The same goes for the other material - it's now more negatively charged, and these extra electrons will vacate it at the soonest opportunity.

    victor1985 wrote:I finded a material about radar and learn about PRF and PRT. Seems that single antenna wich emit and receive are problematic because of ambigusity. Mean about the wrong locate made when a second echo is emited after first echo is returning. I will learn about separate emitter and receiver of radar. Also modifying speed of wavelenght would help but dunno if is possible. Or alternate wavelenghts or power.

    I don't know that much about radar, and I can't explain to you how stealth works - or rather I wouldn't be able to do the science justice, with my explanation.

    But I will tell you that the speed of an electromagnetic wave is always constant; that goes for radio waves, infra-red, visible light, etc...

    The difference between them are their wavelengths and frequencies. In fact their wavelengths are always inversely proportional to their frequencies - the greater one is, the lesser the other is.
    This is because of the wave equation; which is basically speed = wavelength * frequency.
    Which means that assuming the speed of the wave stays constant (and it does), then an increase in wavelength must imply a decrease in frequency and vice-versa.
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    Post  victor1985 Wed Mar 04, 2015 4:20 pm

    I finded how error can get on long distance radars. More exacly about the second wavelenght emitted mai get first in front of first wave. Thus a more bigger pause mai be done between them. But can be obtained better acuracy using a known series of different close wavelengts. You know the series you know which wave is first. Just like using different sounds and know whit what started and whats next.
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    Post  victor1985 Wed Mar 04, 2015 4:43 pm

    flamming_python wrote:
    victor1985 wrote:
    flamming_python wrote:
    victor1985 wrote:I wanna ask something: a ampere is a 6,241x 10^18 electrons that are moving throught circuit. Question is: those electrons where are they after moving? And a coulomb is stationary electrons..... where they stay in a battery and in a electric circuit togheter and separate?

    They all move 'round a circuit. 'Round and 'round they go. So eventually, after some time, you'll see the same electron passing the same point in the circuit as did before.

    Coulomb is equivalent to 6,241x 10^18 electrons, they can be stationary or moving, but I suppose it only really makes sense to talk about coulombs when they are moving - as when they are stationary the circuit is not charged at all and no electricity flows.

    As for where the electrons stay - on the outer shell of the atoms of the conductor. That's where they are at rest. When you apply a voltage, they start hoping from one atom to the next - all in the same direction, and this is what electricity is.
    The larger the conductor you connect to the battery (i.e. a longer wire), the more electrons in total would be moving.

    so a battery  what makes whit that plates inside if the curent is given by the electrons in the wire? What is their role? To create the electric field that push the electrons?

    Yes, exactly that. The battery's chemical reactions create a difference between its two terminals, one ends up being more negative (more electrons), the other more positive (less electrons).
    When you connect a wire to the two terminals, the electrons in the wire will be attracted towards the positive terminal and will move towards there, giving you a current.

    victor1985 wrote:More clearly i do understand the coulomb  being the static electrons wich are POTEBTUALLY moving and become electric curent. Is like a capacity of body but not yet functionally. Is like saing: if i thrown a rock whit 10 metter/second i can obtain a kinetic energy of x, but i have not yet thrown the rock, but the rock has the potentually force to do it.

    Electrons always have the same charge, it doesn't matter if they're moving or not.

    Coulomb is just a unit of measurement - it's literally just equivalent to the negative/positive charge of 6,241x 10^18 electrons/protons.

    But at the same time, it doesn't really make sense to speak of coulombs it unless a current is flowing. You don't really use this term to talk about anything other than electricity (i.e. moving current). When electrons aren't moving, and there is no electricity - the electrons still have charge, but the conductor itself is not charged - as the electrons are fixed in orbit around atoms, which are neutral, and the end result is that the entire material is neutral and has no charge.

    If you want to talk about electrons in isolation (like when they are moving through space at close to light speeds), then you use the unit electronvolt to talk about their energy level - which is a slightly different concept but related to that of coulombs and charge.

    victor1985 wrote:As far as i know coulomb is the unit measurement for electric charge. Which i do understand as being static atoms (pozitive or negative). The intensity is measured in amphere and is the electrons that pass by a conductor in a second. What do i dont understand well is the difference between electric charge and intensity. Point is i dont understand STATIC ELECTRICITY at all. Better i understand electric circuit.

    Static electricity is just what happens when you have two locations seperated by an insulator, that have different levels of electric charge. So exactly like how a battery works.

    The electrons balance themselves out by transfering from where there are more of them to where there are less of them. If the difference between the charges of the two places is great enough, the voltage (electromotive force) can be high enough to cause an ionization of the air between these two places (if air is what seperates them), thus temporarily making air into a conductor, with the electrons leaping across it in the form of a spark or electric arc.

    Of course, as soon as the balance is restored and both locations have the same charge - they are electrically neutral and no more current flows. In the absense of a chemical reaction that keeps creating such a difference (i.e. like the one in a battery), there will be no more sparks or electric arcs after the initial one. It happens momentarily and that's it.

    Usually the way such a difference is caused, is by rubbing some surfaces onto certain materials.
    Doing so can rub some electrons off the surface, and thus cause it to be positively charged. As soon as that material touches something else, especially a conductor - the spark happens.
    It can happen to human skin too, which is why humans sometimes get zapped by static.
    so let me understand well: in a battery the chemicals rip electrons from pozitive head so in this creates trought the heads and conductor of circuit and endless no balance of electrons ie the electric current? So how batteries loose power trought time?
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    Post  flamming_python Wed Mar 04, 2015 7:37 pm

    victor1985 wrote:so let me understand well: in a battery the chemicals rip electrons from pozitive head so in this creates trought the heads and conductor of circuit and endless no balance of electrons ie the electric current? So how batteries loose power trought time?

    Yes pretty much, I don't know the precise chemical mechanism but yes electrons congregate on one terminal which leaves the other one positive, and this creates a voltage difference between the two terminals which is enough to drive a current when a wire is connected to both terminals.

    The batteries lose power because that chemical reaction is not endless, like any chemical reaction it gradually dies down and then it ends, no more electrons transfer to the negative terminal, thus there is no potential difference between the terminals - and no more voltage to drive a current.
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    Post  victor1985 Thu Mar 05, 2015 12:37 pm

    flamming_python wrote:
    victor1985 wrote:so let me understand well: in a battery the chemicals rip electrons from pozitive head so in this creates trought the heads and conductor of circuit and endless no balance of electrons ie the electric current? So how batteries loose power trought time?

    Yes pretty much, I don't know the precise chemical mechanism but yes electrons congregate on one terminal which leaves the other one positive, and this creates a voltage difference between the two terminals which is enough to drive a current when a wire is connected to both terminals.

    The batteries lose power because that chemical reaction is not endless, like any chemical reaction it gradually dies down and then it ends, no more electrons transfer to the negative terminal, thus there is no potential difference between the terminals - and no more voltage to drive a current.
    well i wanna ask :in a car battery there are permanently electrons rip by the chemicals or only when you start the car? The key that you rotate when you start the car what does connect wires from battery to engine in which the curent goes to engine?
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    Post  flamming_python Thu Mar 05, 2015 11:00 pm

    victor1985 wrote:
    flamming_python wrote:
    victor1985 wrote:so let me understand well: in a battery the chemicals rip electrons from pozitive head so in this creates trought the heads and conductor of circuit and endless no balance of electrons ie the electric current? So how batteries loose power trought time?

    Yes pretty much, I don't know the precise chemical mechanism but yes electrons congregate on one terminal which leaves the other one positive, and this creates a voltage difference between the two terminals which is enough to drive a current when a wire is connected to both terminals.

    The batteries lose power because that chemical reaction is not endless, like any chemical reaction it gradually dies down and then it ends, no more electrons transfer to the negative terminal, thus there is no potential difference between the terminals - and no more voltage to drive a current.
    well i wanna ask :in a car battery there are permanently electrons rip by the chemicals or only when you start the car? The key that you rotate when you start the car what does connect wires from battery to engine in which the curent goes to engine?

    Electrons aren't "permenantly ripped". Listen, go back to all that I wrote and read it again. I won't repeat anything for you, everything's written down already.

    As for what happens when you start the car - well I assume the battery is used to power an electric motor to start the engine.

    I doubt that the key rotation connects any wires; it just flips or connects a switch I would assume, that when connected completes the circuit; allowing current to flow to the starter motor.
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    Post  victor1985 Fri Mar 06, 2015 2:02 am

    A now i got. Are ripped once but is a infinite loop in circuit.
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    Post  victor1985 Fri Mar 06, 2015 7:12 am

    Just i was curious: after the electrons start looping the curent stop at a one specific moment?
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    Post  victor1985 Wed Mar 11, 2015 9:58 am

    I read somewhere that USA want to improve defense of A10-thunderbolt ii against MANPADS. I readed something about DIRCM pods. What they are?
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    Post  Werewolf Wed Mar 11, 2015 10:05 am

    victor1985 wrote:I read somewhere that USA want to improve defense of A10-thunderbolt ii against MANPADS. I readed something about DIRCM pods. What they are?

    Probably something like AMASE/DIRCM pods.

    They look like that.


    Pods with extra sensors that can detect Missiles that are incoming to the jet/helicopter and those sensors can detect missiles due the IR/UV spectrum of their exhaust plume.

    http://www.terma.com/media/90427/terma_update_july_2006.pdf


    Last edited by Werewolf on Wed Mar 11, 2015 10:06 am; edited 1 time in total
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    Post  victor1985 Wed Mar 11, 2015 10:06 am

    But now USA utilize something else like f22 and f35. Can be maked a aircraft totally invisible? Against visible light (are some researches for materials that bend the light), against radar ( can a aircraft have composite materials that totally absord radar waves?), against IR (can the flame be covered by something?) and against noise?
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    Post  Werewolf Wed Mar 11, 2015 10:09 am

    victor1985 wrote:But now USA utilize something else like f22  and f35. Can be maked a aircraft totally invisible? Against visible light (are some researches for materials that bend the light), against radar ( can a aircraft have composite materials that totally absord radar waves?), against IR (can the flame be covered by something?) and against noise?

    Nothing can be made invsisible, there will be always some electromagnetic spectrum where you always have reflection, regardless when you make it invisible in the human eye spectrum, there will be still exhaust gases and radar spectrum along with far to ultra radar spectrum, which is not used today in army, but when their radar spectrums for detection deplets they will expand in other spectrums. Nothing can be made totally invisible against everything and anything, there is always a spectrum you can detect it.
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    Post  victor1985 Wed Mar 11, 2015 10:14 am

    That supposing that ultra radar spectrum cant be absorbed by composite? Cause in this will be a battle who gets the larger spectrum and who gets the composite materials. As far as i know more you go ahead to gamma ray nothing can stop.
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    Post  Werewolf Wed Mar 11, 2015 10:16 am

    victor1985 wrote:That supposing that ultra radar spectrum cant be absorbed by composite? Cause in this will be a battle who gets the larger spectrum and who gets the composite materials. As far as i know more you go ahead to gamma ray nothing can stop.

    Today it is much easier to use different spectrums for detection than developing new materials in high enough quality and quantity to use against those spectrums.
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    Post  victor1985 Wed Mar 11, 2015 10:18 am

    Yes but nothing guaratees that doesnt exist a supreme composite material.

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