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Basic Physics III Lecture 22

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Automatisierte Medienanalyse

Erkannte Entitäten
the we don't talk we will stop today our discussion with a talking about the nature of orders of
Arbitron look like knowledge to look it up in the air in global images you find something like this it's a blue ball that he might miss printed on it but that's of course not on our strong can't really see of knowledge from the end of we last lecture we actually found out that it is quite easy to make electron waves much shorter Rayburn most of the race so I can't really see an hour from on comes just measure the effects of and it has a definite must for 9 . 1 times tender 1 31 kilograms or in terms of energy overseas 500 case and it has a challenged error messages elementary charge minus 1 . 6 times 10 to the minus 19 too long and indeed it has summer intruders Adagu momentum that it's almost like the it was swimming or risks and and it is both particles was away and finally a hairy on wants to take a Christian literally turn orders of the nature of our top electron the week worked for and that's that's what the reason why we use Allah triumph for that Honda going the 1st electric experiments carried using pieces of cat fur since we know all that electrolysis or waves among other things that means that it is it ought to be possible to construct an optical instruments of the electron there was an ideal from this from or that it ought to be possible to construct magnetic lenses meaning error aromatic oils that produced medic fields so that electrons that Our affected by those magnetic fields behave very similar ways that photons behave when it passed through a lenses and therefore this was a theoretical ideas but because the Ehrlich from Raven even for modest acceleration voltages so far smaller than that of some of light of optical light the airborne can theoretically at least achieve much greater magnification out from microscope and with a light microscope and so this idea was eventually developed by this fellow who eventually got away prize for a modern instrument up to a thousand times better than light microscopes and still limited by operation effects rather than he really resolution criteria so that that is where huge success story not only can you Lake of transmission electron microscope alike like this 1 which is modeled after the light microscope so wary hair but a source of our Soros be there make apparel being of the use of condoms and where we have the objective lens and if I may have DIP east and project the image on some screen filled conducted Tech but we can also construct a different type of microscope will
balance the electron off the object of this case he steal from being scattered across the specimen and that was once you hit the specimen role in the story of from which Richard tech and then you could use a computer to for use an image of and the advantage of that procedures although it has somewhat less resolution to retrieve the transmission microscope it gives you a three-dimensional junk already gives you a tool of
beautiful images of virus what are attacking our arterial so this 1 as a transmission picture of this comment from a scanning microscope and you can see incredible detail you get from the viruses the dollar bought 2 of 3 dimension eyes application off we nature of a look into technology sonar that to
that led us as discussed something very fundamental structural that since about the beginning of the 20th century we know that all matter that Renault made out of our at those atoms that were not like originally Sonter really are indivisible and the fundamental as are still used in chemistry but they have a structure themselves the 1st hint of such a structure came from experiments in the the 19th century Ranariddh Thomson discovered the Ehrlich so as small negatively charged particles and so we made on after model based on that sometimes referred to as the model and so he assumed that hair small negative charges that are embedded in in solemn extended positively charged material and as such an entity forms of matter and it is held together by the electrostatic force between negatively charged electrons with positive charge material rather Florida New Zealand fell over and he put that test and he was a model and he was shooting alpha-particles was positively charged particles on a metal form and if this correct than what you would expect it's the alpha-particle then it sort of just chaos will be out of and goes through pretty much undisturbed because the electrons will just pushed out of the way the alpha-particle is much heavier and through his great surprise at his ranch and gathering of up alpha particles and even reflections of the alpha particles are coming back it was very surprised by that I believe you knowledge life food in the big Cat a piece of paper and see the cannonball reflect back and so what is reason that this novel cannot be correct in this former rather positive Charles that has to be concentrated your In a comic look like so that is much much smaller than an apple and only then doesn't have enough charge Mast to actually interact with the alpha-particle forever the model that have atomic nucleus on the order of 10 to the minus 15 meters and Adams however diameter on the order of 10 to the minus 10 5 orders of magnitude smaller and then Alec a clouds of broadening his personal and make that neutral and this was a further refine born some from Bayern equally sued the ELECTRONIC orbiting around Tokyo in a similar way as a planet's orbit around the sun so kind of like miniature merciless this is how this would
work a charge North Korea discharged by here ever elementary charged capital Z depending on which element and then if you consider just 1 hour on there is of 4 attractive force between the hour on and we don't clears the electric force purchases on the magnitude of it is given by NYTimes elementary charged the charge of good times the charge of electrons which is also the government divided by the distance Carrera divided by 1 4 part not if he is still a circular orbit and air initially some of photos of elliptical orbits just like in the solar system but if they make the simplifying assumptions that the orbiter a circular then we can actually sold the problem classically service centripetal force and then out from the velocity remained stable in a circle around no clear and we need a balance there's this electric forms requires centripetal force and can sold but for 80 years off and and get some solution however for this solution to make sense with experimental data 1 needs to require that only some lady ion possible if not all of them and the questioners wife and a mother of 2 medical problems with axles Croatia if you have relic from wooden around the where America looked at it from the side that looks like the autonomous sort of the planet plane firms were just oscillating back and forth Soviet oscillating job and it ought to emit radiation just like any oscillating charge she and when it doesn't amid radiation and loses energy and therefore it will moved closer to a mail which makes it go even faster oscillating fast and that means that it emits more radiation so basically should just spiral into lucrative and absorbed by and such a thing does not have a Adams don't a destroy themselves and radiation catastrophe and the question again wife not bath so we can
use we concept of electrons as late particles to rescue so we observe that electrons note from propagating then it has some wavering slammed overtures given by by the constant divided by the momentum of the or the time constant divided by the Sierra muscle theology turns its velocity and if the propagation is a in straight line than me so have a traveling wave like that and if we fix the lying on both ends and get a standing wave and only certain wavelengths are possible just like the waves on the strength in this case we have a circular orbit so we have a different kind of boundary conditions if go once or on the orbit then the phase of the wave has to match itself and therefore since we know it he then conference circle 2 part-time radius this this this must be earned integral what times the wavelength otherwise we get destructive interference like in this case for example and since it keeps running around and around and around the destructive interference will be complete if any of it apparent so we get only stables a solution for a standing wave on on circle if we have this condition meaning there the distance along the circumference of a circle an integral number and around and if value was expression for the wavelength the ELECTRONIC then add at Lander equals aged over momentum we're momentum last time velocity then we get the condition that the radius times I will try best times its velocity must be an integral number times from constant in right to High which Chris constant age-old too and usually referred to on that can look at this this condition in a different way when observe that and must times velocity is momentum distance from the and all times our momentum for our times must velocities the angular momentum of the Isle of Palms with respect so that Angulo Tony called fell in general always related crossed and took us into a linear moment so in this case we just opened 1 component and get this so we find that From Alda requirement that we have a standing from ways we get we find that only certain quantized values of went on so in a very similar fashion as we had a quantized fear energy off from the field of the year and vibrations of molecules in the black so if they now use this condition and sold it for the velocity of simply sold this equation for the velocity which means divide by the radius and last get for the velocity that it's an H-bomb divided by ladies and we can alter firms that in 2 or 3 years so if you wanna know what is every EDB square off purchase where we have fallen for somewhat for
that criterion really good MTV square off to annul you lose the equation
for for the velocity for coming from a standing out from the families grow on me on terms and derided by Amy square and therefore we get a lot of the MEL cancels meeting these Graf is equal to end his career each basket turning off and can uh said that in relation to be electric force this is the term from electric for us once we do that we have an expression that that tells us what radius is possible and would really not possible because of that standing wave conditions not already DIR possible and 1 from across Romania ATI eliminated by destructive and and that sort of of explanation for why only lease as certainly not so we have to add basically a quantized radius the radius has be ends career at times age fast career multiplied by a full pipe not over any disease off the air the end radius is given by the 1st radius times and screw always where the 1st recently use and equals 1 man in this expression and the integer and is called the Quantum number because described the state offices so the value for his 1st radius which is also called the ball a radius of 50 2 . 9 2 with 2 commuters or 0 . 5 2 9 times 10 to the minus 10 meters and now you remember that I told you the actor has roughly the the size of 10 to the minus 10 meters twice this we can also look at this expression for of the for the ball radius in a different way and we knew their product cool factor was the first one this and this this is the 2nd 1 and the 2nd 1 3 recognized 3 Compton wavelength of the electron somebody from the last lecture and the 2nd constant that's actually new constant and that it is usually called Olaf or fine structure constant and it's has no you so it's relatively easy to remember 1 well from his roughly 100 it is only calculated with Konstance of nature it is a constant of nature itself also and in fact it characterizes the strength of electromagnetic force so add another words he gets that radius this year Compton wavelength of electrons divided add to high times the the fine structure constant we can also look at these electron energy that results from that now that they have found which radio possible he can also find what energies of possible and we have to tides of energy comedic energy and potential energy and therefore simplification we are going to use nonrelativistic approximations rather than doing a fully relativistic fiction this summer so we simply say the kinetic energies one-half hour on last time velocities and from the expression of hair for the velocity this is 1 half times quantum numbers Korea Times H. basket derided by any asked so we simply have not been told about this equation seek special for me arrived earlier so if they now use a condition which may be possible for his ask get a all radius Scalia derided by disease time to condoms what the power and that means that some of the quantum number powerless and H-bomb policy canceled and left the one-half disease where each basket divided by iii ends Grover quantum square times for grip and if we now find what is the outlook from last time will raise his career and come up with this and finally air plodding all they get this expression for the kinetic energy child look times Marcel Trondheim elementary charged for power and then in the denominator each basket of the quantum numbers career and some prefect of from the a electrum McClintock for us then for the potential energy actually much simpler for the potential energy and revealed that the potential energy of you often electrons which has charged minors e enough voltage is given by the simple expression and we know all that these voltage produced by bar the book Lewis charge of the clear multiplied the elementary challenge divided by war I have not been to the radio slower she was that there potential energy use is given by this expression and if you plug in the novel for the war rages we find out after some complicated matter that us exactly twice the kinetic energy therefore if you add up the potential and the kinetic energy of minus Vice time and became a big energy plaster kinetic energy just miners once kinetic energy we simply have to take this expression put a minus sign in front of it and we get the total energy and you can express that the child of the nucleus square divided by the quantum numbers Korea times another ponds so-called Rick but energy where but energy is given by if expression or are in units of the fine structure constant reminders of square can be arrest energy of the electrons divided by 2 or if you prefer a numerical value but energy is minus 13 . 6 1 0 it is the the ionization energy off of hydrogen that we need to calm this much energy into reality on a bouquet ejected from out of the hydrogen solar in summary that using standing electron waves of quantized the radius and you find on those lady possible lowest honestly the ball radius roughly 50 feet because of quantized the energy are with me ionization energy being about minus stood 6 electron volts and of quantized the annual and because it is a standing wave we have also sold the 2nd problem of the model since the wave is a standing wave it means that on average the ELECTRONIC dozens Woodall 1 world's this wave around this way and condo is going wrong that way so sum of both ways results in no emotion as we are Charles doesn't move on average and doesn't emit an irradiation as long as those conditions so aware of his mobile isn't perfect and you'll talk about is inadequacies leader but it captures menu of b but it's
really happen you can also look at the UCI
Demel website and you find out that they can get the whole thing is very easy which mission
celeriac hydrogen and if you want Healy on the slowness helium or neon but it was mentioned solely on excellent because that's Muzio irony and the further removed on the periodic table of the more complex an early in the structure but some of those spectral becomes and you can also measure those the lines in some sense if you click on 1 of them will show Liu and units of angst remote 10 to the minus 10 meters what a wavelength of this on this particularly line want to cool down only so let's see whether we can actually understand those atomic spectra so that the way we make those lands as we rarified gasses and we operate them and high-voltage discharge tube and then be accelerated childless in as they excite the atoms to radiation and mediate with the characteristic frequencies that was a banned from this check trauma dust which is basically with the diffraction grating want what we just did we can expect a spectrum characteristic for the element 1 can use a continuous spectrum the soul of black bodies From and Parsifal gas like gas surrounding the sun and you can then find an inverted image or of absorption lines coming from the various elements and be a little out Leopard depends which wrong between absorption spectrum and emissions show in other words spent reactor absorbs radiation it absorbs address the same frequencies as that mix 1 can no go through a enormous task of making a catalog of the various alliance that respect from machines for example trend here is just for 4 hydrogen assembles a so-called serious Lyman series the bomb was serious passions series in various parts of the electromagnetic spectrum each 1 of them liar consist of a whole bunch of mine for example is a woman on the boundless series conceived in more detail eventually almost by chance must figure or the underlying ruled behind so the difference among CONFLICT tool following off the inverse Of the wavelength is a constant off times 1 0 and Prime's Korea minus 1 0 Malinsky for any equal 1 you recover the Lyman series an equal tool recovered series and full and a closely a culinary passion show this constant Calderwood constant and you can determine if experimentally and has gone so with this lobby can explain emission lines of hydrogen so if you look at this as a constant here value and if you multiply adrift the plant constant the speed of light and you get a 30 . 6 up about 1 hour from so that this leader saying constant regard for the ionization energy of hydrogen so in other words but energy is nothing but minus the constant times each currency so are constantly act ionization energy of hydrogen that means that we can sort of a picture of how this from being f so we know that have from when we
calculated the hydrogen and we know that the air the energy levels of the hydrogen and off and other matters on the Aziz Korea Times this would but energy he lies and script so we can have sold off a lot as a function of you can plot the varies energies and defined facing like that and we can now understand various spectral lines the transition between those energy level and that is because it's this transition that is why we get the difference between those numbers and and prime script because those are referred to the energy levels and have so if you wear make a transition from 1 energy level toe another energy level then simply by sitting here energy equal to uh each time the flight frequency can calculate and this is why the tho constant and ionization energy related by HC simply conversion from from energy to them wavelength so let's look at that In an
example so let's see that determine the wavelength of the 1st Lyman line so that the transitional level tool to level 1 and the questions also on what regional Elektra we can't expect from a located the sole theirs set the dude difference H. times be frequency reaches the constant solar the energy differences difference between 2nd and 1st energy level that this might mislead . 4 electron volts which leadoff dysgraphia and equals to minus 13 . 6 electron volts which is the lowest level the ionization and to get there for 10 . 2 0 at Trumbull differ now take those 10 . 2 Alec an hour formal HCE over attempt on toe but tumbled reach sees 1 . 2 4 0 0 From Micro we get 120 tool not only and that this in ultraviolet portion of the year I can't expect all weekend directly go to alleviate Gould and simply Garrick Utley was 1 lavender using the constant and then times 1 0 1 square minus 1 mobile for 1 of 2 career and this gives us again 120 I wanna 122 not so that still another example and cut their determine the wavelength of the 5th bomber line that transition from levels 6 level 2 and again questions what Farber the electromagnetic spectrum so at this time I'm just going to used view from constant the retard constant and I have to subtract 1 all war 2 square minus 1 36 from level 6 and I get 410 and not only 801 once 1 of its expression and 410 not only does this violent life the 5th ball maligned is indivisible part of that and
let's also look at the maximum wavelength that hydrogen in its ground state can absorb he said that the rule is that electromagnetic energy that EPROMs absorbers the same line as meeting so another words the longest labor and the smallest amount of energy and since sitting in the ground state the smallest amount of energy the 1 that will lift it from us the lowest level of the first one high up so it's the 1 true transition again and we already know all that what energy that corresponds to word brave corresponds to From the previous example 120 on the question is what would be the next smaller wavelength after that and that would be the 1 transition and in this case it's a 13 . 6 electron volts minus 1 . 5 from the leader of this graph and so that gives us an energy difference of 12 . 1 0 at World War wavering from 100 to another and
finally it's calculated the ionization energy of helium plots rather than hydrogen and calculated also the longest wavelength to IMS billion-plus so in this case as since we all energy levels of given by disease career times but energy and divided by the novel square and we assume that ionization energies and look at the ground state saw cause a lot vehicles tool and because as equals 2 of his gives us 4 times 13 . 6 I would be a burden or minus 54 . 4 and the level of the ground state and therefore the ionization energy of feeling last is 54 . 4 hours on end if you want all wavelength required to carry such an energy recently used plant constant for that kind of its 22 . 8 not at the very end I'd like to show
you assimilation of
hydrogen out here using me a time for some of the model and so right now be
looking at the 1st Albany the ball radius or from running around in the particle protection for them is a we can look at she said the latest picture and the rate of looks the Crimean this case is I was just 1 wavelength superimposed on a circle however if goal tool higher levels that saved you go to level No. 6 from now we see that they are from all returned man were finally there needs itself and the the referred please Conde conditions so this is how it looks like wave model and if you look at the at the particle model that matter since the ELECTRONIC further however a smaller velocity and is moving slowly around the nucleus so I told you that this model is quiet the entire truth and part this is because its two-dimensional all everything happens in the plane and there in reality areas spherical symmetry around the look still and look at the full simulation of the
hydrogen different and job
let's look at the 6 all but again and it is actually a standing wave and we dimensions now or area was on crease position him so the color and the pictures shows of the pays off the wave a three-dimensional wave oscillating back and forth on standing wave can't Norwood surfaces which not ocellated all this is the same level that we looked at reform but however In the case of a dimensions they actually more quantum numbers and we discussed so weak that we just discussed 1 quantum number which give the remained energy level this is the quantum number and if we mention there also a quantum numbers associated with it angular momentum riches show called L & M so let's looked at it and increasing 1 for health so the first one is usually called S where the spherically symmetric 1 the 2nd 1 is called key and now you see a lot more complex structure has a hand for simple spherical won the NL preferred directions that new rotate accordance we can go to the next 1 and look the next higher quantum number that gets more complex is called D and finally an F for those actually quite pretty picture and day look what can I do such calculations to understand the chemistry of various elements as that kind of like a symphony of quiet after that as of city neat now would you think for atoms Melita look like nature so resonances and I'm standing waves are wary of our core call understanding how even when you
use the full of full cultivation of just theater the simplified some think it will attend
Magnetisches Dipolmoment
Drilling <Waffe>
Angeregtes Atom
Natürliche Radioaktivität
Coulombsches Gesetz
Drahtgebundene Übertragung
Relativistische Mechanik
Puma <Panzer>
Elektrische Ladung
Blende <Kleidung>
Optische Dichte
Quantisierung <Nachrichtentechnik>
Front <Meteorologie>
Phase <Thermodynamik>
Scheinbare Helligkeit
Source <Elektronik>
Erwärmung <Meteorologie>
Flüssiger Brennstoff
Optisches Spektrum
Fiat 500
Walken <Textilveredelung>
Konverter <Kerntechnik>
Flavour <Elementarteilchen>
A-6 Intruder
Elektrische Ladung
Magnetische Kraft
Ohmsches Gesetz <Elektrizitätslehre>
Optisches Spektrum
Kaliber <Walzwerk>
Experiment innen
Halo <Atmosphärische Optik>
Titan II
Ultraviolett B
Direkte Messung
Buick Century
Schutz <Elektrotechnik>
Source <Elektronik>
Masse <Physik>


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Titel Basic Physics III Lecture 22
Serientitel Basic Physics III
Teil 22
Anzahl der Teile 27
Autor Smy, Michael
Lizenz CC-Namensnennung - Weitergabe unter gleichen Bedingungen 3.0 Unported:
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DOI 10.5446/12958
Herausgeber University of California Irvine (UCI)
Erscheinungsjahr 2013
Sprache Englisch

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Fachgebiet Physik

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