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Sensei

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Everything posted by Sensei

  1. Java has JIT. http://en.wikipedia.org/wiki/Just-in-time_compilation
  2. Distillation of pure methanol, ethanol, isopropyl, or with mixture with pure water should give you just initial alcohol. They will be first flowing because they have lower boiling point than water (methanol first 65 C b.p, ethanol second 78 C b.p., isopropyl last with 83 C b.p.). That's why we have to flush away the initial result of distillation of home made moon shine, because it's methanol. We don't know what source of isopropyl you used. You should check out label to learn what it contains. We don't know in how clean environment you were doing distillation... Did you use glass or metal bulbs and pipes? What metal(s)? Take photo of setup, it'll be easier for you and us to tell.. Bought in chemical equipment shop? These tend to be made of heat resistant glass, with small capacity, but chance to contaminate is minimized. Bought in shop with alcohol distillers, etc stuff.. ? These tend to be made of copper or special steel, and aimed to distillate just moon shine ethanol, not general purpose distill. Or built by yourself?
  3. The same is with any macroscopic object - you have to stop it from moving to tell exactly where it is (with great precision f.e. 1 mm or better), and then we know that its momentum is 0 and position is exact.
  4. "Thanks for registering Your account has been successfully created, although it is not yet active. In order to activate it please check your email in a few minutes for our welcome message and follow the instructions in it. Please notice that we only allow one membership account per email address. This pre-registration email confirmation step will expire in 48 hours. If you do not confirm your email within that time, both your username and the specified email will become again available for new registrations." This is message I received..
  5. Where did you get such idea? When electron annihilate with positron gamma photons are produced. Then gamma photons can be absorbed by some charged particles and new bunch of photons emitted with lower energy, lower frequency.. And after a while energy that was in electron and positron is spread in millions or billions of other particles.. Susskind proposed multi universe idea as explanation of why physical constants have values, as they have, in our universe. Who is believing in it, won't be searching for sense in why physical constant have value as we measure.
  6. Elite Engineer, EdCarl, where did you get isopropyl that is not pure, so you have to distill it?! In any electronic shop you can always get 99.9% pure C3H8O... http://en.wikipedia.org/wiki/Isopropyl_alcohol It's essential thing to run cloud chamber. I have liters of it: It costs 5$ for 1 L.
  7. If you have star with initial mass m, after burning out all fuel and collapse it's mass is smaller than initial m. During lifetime star is ejecting clouds of gas/plasma in eruptions.
  8. Distance between Earth and Sun is ~150 mln km..
  9. If teachers are learning just theory, make electrostatic machine by yourself, and show class.. You can get better grade. See video http://www.youtube.com/watch?v=Zilvl9tS0Og
  10. Electrostatic experiments are boring? Cut paper to pieces 1x1 mm, 100 pieces. Then rub some glass tube on fabric, and touch paper pieces. They will stick to glass tube.
  11. I think many depends on teacher. If I would be learning in school, I would be showing cloud chamber, electron gun, Crookes tube. Showing what happens when there is electric and magnetic field around them etc. etc. Showing how to create high voltage, electric arc, vacuum arc. Nothing stops you making them by yourself.
  12. Before you learn running, you have to learn walking..
  13. During measurement at macro scale we are changing state of measured object as well. But this change is so meaningless small, that nobody ever think about it.. f.e. you want to measure temperature of water putting normal Hg thermometer to it. Accelerated molecules of water are colliding with Hg molecules, giving Hg energy, and are loosing energy by them self. Hg is changing volume, and we are reading new Hg volume from scale. Hg is never returning energy that it took from water back to water! So water permanently lost this energy - by measurement we changed state of measured object. Made water a bit colder. Measurement at quantum scale is so dramatic it changes state of measured particle permanently.
  14. You cannot make gas from plain photons. Gas is one of state of matter, and photons are not matter. The simplest gas is made of Hydrogen with temperature at least 20 K. Whether some matter is in solid state, liquid state, gas state, or plasma, depends on velocity of particles/molecules (so energy that has been absorbed by them). Gas can be turned into liquid by taking energy from it, then we can take more energy from it, and it'll turn into solid state. Photon is electric neutral particle. Energy of electron is 510999 eV. When electron is colliding with positron, there are created two gamma photons with 510999 eV energy each. So mass of electron and positron during annihilation is converted to energy of these new photons. 510999 eV / 4.135667*10^-15 eV*s = ~1.23559*10^20 Hz (Compton frequency) It was energy in unit Electronvolt (eV). In Joules: 1.23559*10^20 Hz * 6.62607*10^-34 J*s = ~8.1871*10^-14 J E = m*c^2 so m = E/c^2 m = 8.1871*10^-14 J / 299792458^2 = ~9.11*10^-31 kg And it's mass you can read on wiki page of Electron http://en.wikipedia.org/wiki/Electron
  15. When one group of molecules (solid state object A) collide with other group of molecules (solid state object B), one gives energy to the other, heating it. Conservation of energy happens at quantum scale. When your hands are cold, you are starting rubbing one on the other hand, and feeling hot between them.
  16. Nonsense. Imagine two metal plates inside bulb with evacuated air. Simply saying the simplest and the earliest version of vacuum tube - Crookes tube http://en.wikipedia.org/wiki/Crookes_tube You can apply voltage to these plates only to some point, after exceeding breakdown voltage with high enough voltage, free electrons are starting flowing between plates (vacuum arc appears) and we can see them because they emit photons like you can see on this picture. In vacuum capacitor distance between plates are minimal (in Crookes tube from picture it's good 20 cm), and voltage is smaller in comparison to Crookes tube which need thousands volts to start emitting electrons between plates. Traditional capacitors like electrolytic after using too high voltage, are permanently damaged. Perhaps vacuum capacitor can survive it, because it's just emitting electrons to other plate.
  17. Rajnish Kaushik, we cannot change laws of physics just like that. Older researchers made measurements and basing on them created mathematical formulas describing what they measured. It's repeatable by everyone, everybody are receiving steady expectable results, so it's law in physics. But new researchers can find situations when measurement doesn't agree with old physics law. We call it violation. They're very rare. Otherwise they would be noticed immediately by original researchers that formulated law. Instance of violation of law is "Violations of the lepton number conservation laws" http://en.wikipedia.org/wiki/Lepton_number On wiki page http://en.wikipedia.org/wiki/Baryon_number you have brief information about hypothetical violation of Baryon number conservation "The still hypothetical idea of a grand unified theory allows for the changing of a baryon into several leptons (see B - L), thus violating the conservation of both baryon and lepton numbers.[1] Proton decay would be an example of such a process taking place, but has never been observed."
  18. It's not just a home toy. It was used to discovery many particles positron, muon, pion and kaon to name a few. Indirectly see result of x-ray ionization.
  19. I would suggest you to get familiar with Cloud Chamber http://www.youtube.com/watch?v=Efgy1bV2aQo http://en.wikipedia.org/wiki/Cloud_chamber It's the cheapest particle detector you can build for less than $20 (mine has 40x25x25 cm so it's quite big). Single usage for a few minutes cost me $3.5. You can also make electron gun, and start "shooting" electrons to cloud chamber. To create high voltage there is needed array of capacitors 400 V, better electrolytic, and a few rectifying diodes. Total cost $30 here.
  20. 1 cm^3 of air has ~2.68*10^19 molecules at 0 C, s.p. 1 cm^3 of water has ~3.345*10^22 molecules of H2O. Collisions between cold object molecules and water molecules are more probable than collisions with rare oxygen & nitrogen molecules. In thermic cups and thermoses there is even used layer of vacuum, to separate hot/cold content from environment.
  21. http://en.wikipedia.org/wiki/Marilyn_Monroe Marilyn Monroe "born Norma Jeane Mortenson; June 1, 1926"
  22. Marilyn Monroe in 1935 had 9 years.... She traveled back in time too?
  23. In Special Relativity you cannot accelerate massive object to light speed. You would need infinite energy.
  24. But he wants high voltage in the first place. High capacitance often goes with low voltage.. What you showed K2 series has just 2.7 V.. He could just use battery instead, result would be the same.
  25. 20*1.2 V = 24 V Array of capacitors that are filled when they're parallel connected to DC, and then switching them to serial circuit, is normal procedure of making high voltage from low voltage source. Marx generator is example of such setup http://en.wikipedia.org/wiki/Marx_generator Another one is Cockcroft–Walton generator http://en.wikipedia.org/wiki/Cockcroft%E2%80%93Walton_generator
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