

Lugemata postitus Postitas Walter2 »
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Huvitav, lapikmaa tõestustest leiab ka selliseid väiteid, mida keegi teine kunagi väitnud pole, aga mida lapiklased vastaspoolele omistavad.T25 kirjutas: 17 Veebr 2024, 14:37 Kaht metalli ei ole võimalik niimoodi omavahel kokku peksta, et tihedus kahekordistuks...
Lugemata postitus Postitas T25 »
Tsitaat:Bethe acknowledged receipt of the IBM machines on 4 April, mentioning that the machines had been put to use in implosion calculations. To check the program, Metropolis and Feynman made parallel calculations using hand-operated Marchant machines, staffed by a group of women who were part of the work force of the laboratory. Like the components of a computer, each carried out particular step. Feynman later explained: “We worked out all the numerical steps that the machines were supposed to do - multiply this, and then do this, and subtract that.” He recalled , “[This woman was the multiplier, and [that woman]
was the adder, and this one cubed, and we had index cards, and all she did was cube this number and send it to the next one. We went through our cycle this wayuntil we got all the bugs out.” The human computer actually developed speed -the same as that predicted for the IBM machines. But as Feynman noted, “the IBM machines didn’t get tired and could work three shifts. The girls got tired after a while.
Tsitaat:Any average Joe now has access to a MacBook or PC with millions of times the hardware computing and storage power of the entire Manhattan Project, its affiliated university-based orbital groups, and all its industrial partners of the time put together. Those resources are matched or exceeded by the software modeling facilities available that, essentially for free, give you access toa nalytical power vastly exceeding all the number-crunching physicists in the Manhattan Project. These incomparably superior basic resources, combined with over seven decades of accumulated public knowledge put the amateur modeler light-years ahead of the Manhattan Project at its peak. And if Bethe could rule out ‘burn the sky’ in a few minutes of slide-ruling, a dedicated modeler can crack the secret of explosive fission using the resources listed above
And there is a secret of explosive fission. That much is true. But it’s way different than you might think. We’ve seen that there’s no serious lack of nuclear materials. We’ve also seen that technical knowledge is openly available.
"Half a century of official and unofficial dissemination of information from the nuclear weapons laboratories together with the normal publication processes incognate branches of physics and engineering, mean that much of the relevant explicit knowledge is now irrevocably in the public domain."
(‘Tacit Knowledge, Weapons Design, and the Uninvention of Nuclear Weapons’MacKenzie and Spinard)
More and more countries claim to be joining the Nuclear Club. But decade after decade, nothing gets openly nuked. That’s because it’s not possible. That’s thesecret of explosive fission. Pure FAIL right from the starting gun. But it’s as ecret I can only refer to, not fully reveal. The nuclear powers don’t mind goofups in materials handling. They don’t mind weapons design espionage and technical information leaks. As long as revelations and speculations serve to reinforce the FEAR, it’s all good. But they’d come down hard as nails on somebody who convincingly refuted the entire proposition.
Hästi lühidalt, kuna ei taha postitust väga pikaks ajada, siis jah, idee oli neil selles, et kontrollitud sümmeetrilise plahvatuse abil suurendada tihedust, et nii öelda käivitada ahelreaktsioon.Nagu see, et keegi kusagil mingi metalli tihedust tahaks suurendada..
In atomic physics, the Rutherford–Bohr model or Bohr model or Bohr diagram,introduced by Niels Bohr and Ernest Rutherford in 1913, depicts the atom as asmall, positively charged nucleus surrounded by electrons that travel in circularorbits around the nucleus—similar in structure to the Solar System, but with attraction provided by electrostatic forces rather than gravity
Eesmärk oli tabada aatomit, aga väga hõre on tegelikult aine. Siit tuli ka mõte, et "peksaks" metallid omavahel kokku kahekordse tiheduseni.But popular illustrations are wildly out of scale:
The size of the helium nucleus is about 1 fermi, or 1 fm, which is equivalent to10-15 m. The atom is about 100,000 times bigger than the nucleus, with an atomsize of about 105 fm or 10-10 m.
(NASA’s Cosmos)
So if the nucleus above were the size of a baseball, the outer electron shell wouldbe miles of empty space distant from it.
Lugemata postitus Postitas T25 »
Praegu just loen mitut erinevat foorumit, sõelun läbi lehekülgede kaupa materjali. Tuleb välja, et ca 100 ja rohkem aastat tagasi ei usutud, et rakett võiks liikuda vaakumis. Nimelt arvati, et rakett töötab sedaviisi, et raketist väljapaiskuv gaasijuha avaldab rõhku atmosfäärile ja seetõttu on olemas nö pidepunkt , mille najalt ennast edasi lükata. NASA jällegi väidab, et atmosfääril pole mingit osa ja nende mudeliks on paat ja mees, kes loobib paadist telliskive välja ja see paneb paadi liikuma.Küülaline kirjutas: 17 Veebr 2024, 15:13 Ma igaks juhuks küsin üle, et kas näiteks sidesatellidid ka ei tiirle ümber maa? Ja rahvusvaheline kosmosejaam?
Kui nüüd tuua analoogia paadis oleva mehega, kes kive loobib( raketi heitgaasi juga), siis nende arvates , kui heitgaasiks lugeda kivi, siis see kivi justkui ilma viskamata lendaks nelja tuule poole peo pealt minema ning raketti edasilükkavat toimet ei oleks. Et justkui nagu vaakum "imeks" gaasi koheselt ära ja gaas ei avaldaks mingit edasilükkavat mõju raketile.Free expansion of an ideal gas refers to when the gas expands freely and instantaneously into a vacuum without any heat exchange or work done.
Lugemata postitus Postitas ping »
See on väga hea plaan ja kui ükskord "valgustatuks" saad, siis jaga teadmisi.T25 kirjutas: 18 Veebr 2024, 01:36 ....
Ma ütlen niimoodi, et ma alles mõtestan seda kõike enda jaoks lahti ja ei oska praegu öelda, mis õige , mis vale. ....
Lugemata postitus Postitas kunn24 »
Lugemata postitus Postitas T25 »
Tee selline katse. Võta meditsiinipall, istu rula peale ja viska eemale. Vaata , kui kaugele liikusid. Nüüd võta sama pall, hüppa õhku ja õhusoleku pealt viska meditsiinipall eemale ja vaata , kaugele liikusid.kunn24 kirjutas: 18 Veebr 2024, 10:49 Jõuimpulss
https://opik.fyysika.ee/index.php/book/ ... ction/1289
Impulsi jäävuse seadus
https://opik.fyysika.ee/index.php/book/ ... ction/1290
Misconceptions about recoil
Although energy must be conserved, this does not mean that the kinetic energy of the bullet must be equal to the recoil energy of the gun: in fact, it is many times greater. For example, a bullet fired from an M16 rifle has approximately 1763 Joules of kinetic energy as it leaves the muzzle, but the recoil energy of the gun is less than 7 Joules.
Lugemata postitus Postitas kunn24 »
Lugemata postitus Postitas ping »
See õpik on ju kallutatud, sest sellisest ammu tuntud emissioonivabast sõiduvahendist ei ole seal mitte sõnagi kirjutatud!kunn24 kirjutas: 18 Veebr 2024, 13:06 Kas selle mõtestamise asemel poleks lihtsam võtta kätte teoreetlise mehaanika õpik ja korrakski läbi lugeda? Aru ei pea saama, aga vähemalt saad teada, et selline asi on olemas.
Lugemata postitus Postitas Küülaline »
Ma ei mäleta, mis klassis meil füüsika algas, aga tänapäeval on põhikoolis 8-9 klassis ja räägitakse neist teemadest ka kindlasti. Gümnaasiumis muidugi põhjalikumalt. Kas sul koolitundides see lahtimõtestamine ei õnnestunud kuidagi?T25 kirjutas: 18 Veebr 2024, 11:57Veelkord. Vajab lahtimõtestamist ja seedimist, praegu ei oska kindlat seisukohta võtta
Lugemata postitus Postitas Walter2 »
Lugemata postitus Postitas T25 »
Lugemata postitus Postitas T25 »
Sorry kunn, aga sina olid see mees, kes kunagi arvas, et vahet pole, kas reaktiivmootor asub lennuki sees või väljas, liikuma hakkab ta ikka.kunn24 kirjutas: 18 Veebr 2024, 13:06 Kas selle mõtestamise asemel poleks lihtsam võtta kätte teoreetlise mehaanika õpik ja korrakski läbi lugeda? Aru ei pea saama, aga vähemalt saad teada, et selline asi on olemas.
Lugemata postitus Postitas kunn24 »
Järeldus, vaakumis raketimootor ei tööta
Lugemata postitus Postitas T25 »
Lugemata postitus Postitas kunn24 »
Lugemata postitus Postitas T25 »
Lugemata postitus Postitas T25 »
Tsitaat siis konkreetse ülesande kohta:To start, we must ask what we mean by a variable acceleration. It could mean two things. One, it could mean that we were speeding up and slowing down, so that our change in velocity was not constant. That is not what I mean here. What I mean is an acceleration represented by a power of 3 or more, as in the curve equation x = t3. That means that you take a constant acceleration and then accelerate it. For example, you take your car out on the highway and press down on the gas at a constant rate. If your foot and engine work like they should, you will have created a constant acceleration. Now, take that whole stretch of highway, suck it up into a huge alien spacecraft, and accelerate the spacecraft out of orbit, in the same direction the car is going. The motion of the car relative to the earth or to space is now the compound of two separate accelerations, both of which are represented by t2. So the total acceleration would be constant, not variable, but it would be represented by t4. This is what I am calling a “variable acceleration” here. It is not really variable, it is just a higher order of change.
The acceleration would be represented by t3 if the alien spacecraft had a constant velocity instead of a constant acceleration. An acceleration is two velocities over one interval, so t3 is three velocities over one interval. Or, it is three changes in x over one defined interval, say one second. We can write that as either three x's or three t's, but it is common usage to use three t's in the denominator instead of three x's in the numerator.
The cubed acceleration can also be created in a car, by increasing your pressure on the gas pedal at a constant rate of increase. This will cause a cubed acceleration in the first few seconds.
In engineering, a higher order acceleration like this is called a “jerk” (though it is usually applied to a negative acceleration, as in a jerk to a stop). I call the positive acceleration a cition in my first paper on the derivative, from the Latin “citius”. As in the Olympics motto “citius, altius, fortius”: faster, higher, stronger.
Because this sort of acceleration is often called a variable acceleration in physics textbooks, most people seem to think it isn't constant, and therefore can't be averaged like the squared variable. But higher powers can be constant, if they are created by a constant process like the one I proposed above with the car and the spacecraft. If the car and spacecraft are both accelerating at a constant rate, the higher power total acceleration will also be constant. Just because an acceleration has a power greater than two does not mean it isn't constant. We will see how important this is below.
Kiirendus on 7m/ sekund kuubis. Kopimisel ei tulnud õigesti üle.The entire modern interpretation of the calculus is upside down in this regard! To show this, let us look at the textbook solution of a specific problem:
Given a = 7m/s3 and 2s, find v final from rest.
v = ∫(7m/s3)tdt = (7m/s3)t2/2 = (3.5m/s3)t2 = 14m/s.
Füüsikaõpik, kust näide päris on:Let us look at the textbook's solution. They found v=14m/s, remember? I found 42m/s. I bet you think they are right and I am wrong, but I can prove they are wrong very easily. An acceleration of 7m/s3 must be greater than an acceleration of 7m/s2, right? A cubed acceleration is the motion of an acceleration, so the distance traveled has to be greater. So let us solve the same problem for a = 7m/s2 instead of 7m/s3. Using current equations for constant acceleration, we find
v = at = 14m/s.
They found the same final velocity for 7m/s3 and 7m/s2. That is impossible. An object accelerated to a cube must be going faster at all t's than an object accelerated to a square. That much is clear to anyone, I hope. So the textbook solution is a blatant fudge, one that doesn't even get the right answer.
Lugemata postitus Postitas kunn24 »
Sa ära aja segi staatikat ja dünaamikat.T25 kirjutas: 18 Veebr 2024, 21:39 https://www.youtube.com/watch?v=Gzz-yiA ... pushoffair
Alates 14:25 on siin näha, mis juhtub, kui õhujuga suunata iseenda keresse. Sama asi juhtub ka siis, kui reaktiivmootor paigaldada lennuki sisse, lennuk ei hakka liikuma.
Enamgi veel, president Zelenskõi on lausa otse välja öelnud, et see võib tuua kaasa Ukraina kaotuse sõjas ning Venemaa edasise agressiooni ka muu Euroopa vastu. Eks meie siin Balti mere ääres oleme selles nimekirjas seejuures esikohtadel.
Oleme valmis keerulisteks aegadeks
Olgu kuidas on, võimaliku president Trumpi otsuste mõjuga abi kohe katkestamisest Ukrainale surve avaldamiseks sõja lõpetamise kiirendamise tarvis, võib üht konstateerida ikkagi. Nimelt tema olemuslik isolatsionalistlik, rahvusvahelisele koostööle jõupositsioonilt bilateraalseid suhteid eelistav poliitiline maailmavaade tingiks igal juhul abi kokku tõmbamise ja Putinile Ukraina arvelt mööndustele lisaks samuti NATO kiire nõrgenemise. Nagu teeks seda ka nüüd infovälja lekitatud tema nn kahekihilise NATO idee käibelevõtt. Me peame selleks siin valmis olema igal juhul.
Lugemata postitus Postitas suvaline »
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Lugemata postitus Postitas Walter2 »
Reaktiivliikumine toimub keha masside ümberpaiknemise tõttu, mitte seepärast, et väljuv gaasijuga ''toetub'' vastu atmosfääri ja tõukab end sellest eemale. Rakett ei stardi Maalt seetõttu, et gaasijuga saab end tõugata/toetada Maa pinnalt või atmosfäärist. Impulsi jäävuse seadusest oli varem juttu.T25 kirjutas: 19 Veebr 2024, 03:32 Kunn, ma panin sulle ajaliselt täpselt selle koha, kus toimub "oma purjedesse puhumine". Olgu see ülejäänud video , mis ta on.
Suvaliselt küsiks, et mis tema nägemus on Joules-Thomsoni vaba gaaside paisumise seadusest vaakumis. Vastavalt seadusele gaas vaba paisumise käigus tööd ei tee.
Küsime siis konkreetse sellise näite - meil on maa atmosfäärist väljas orbiidil õõnes silinder ja selle sees on kuum gaas mingi rõhu all. Avame silindri otsas dekompressiooniklapi. Kas silinder hakkab liikuma.
Mina väidan, et vastavalt Joules-Thopsoni gaaside vaba paisumise seadusele, mis ütleb, et gaas vabal paisumisel tööd ei tee, gaasi rõhk kukub kolinal kokku, kogu gaas paneb "whooopsti" dekopressiooniklapi kaudu plehku ning silinder ei liigu. Lihtsalt kogu soojus pani laia ilmaruumi minema. Gaas läks sinna, kuhu oli kõige kergem tee minna. Nagu vedelik või elekter , otsib selle koha, kust on läbi kergem minna. Ja kuna väljatungimisel mingit takistust ei ole, siis mingit rõhku gaasis tekkida ei saa, mis saaks hakata silindrit suruma .
Atmosfääris oleks asi nüüd veidi teine. Paisumine ei ole enam vaba. Atmosfäär tekitab dekompressiooniluugist väljatungivale gaasijoale vasturõhu ning paisumine ei ole selles mõttes enam vaba ja gaasil on võimalik tööd teha.
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