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Everything posted by Sensei
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Mine "aquariums" are: cloud chambers, and other one have several liters of Hydrogen (10 hours of electrolysis of water), and Deuterium for experiments.. You seem to have quite "traditional" usage for aquariums. ps. Lovely fishes, Moontanmen. ps2. You should show what happens when piece of bread is "appearing" in water..
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What is surprising? Inverse square-law is [math]P = \frac{P_0}{4\pi r^2}[/math] so after reversing there is: [math]P_0 = P*4\pi r^2[/math] Energy that we receive at Earth is 1367 W/m^2, so Sun emits energy: [math]1367*4\pi (150*10^9)^2 = 3.8651*10^{26} J[/math] per second in the all directions. Then replace r by distance between Sun and Venus (~107-108 bln m): [math]P = \frac{P_0}{4\pi r^2} = \frac{3.8651*10^{26}}{4\pi(108*10^9)^2} = 2637 \frac{W}{m^2}[/math] Literally Venus receives twice the energy that Earth is receiving per meter square of surface per second. It's just a matter of time when the same will happen to Earth, when radius of Sun will be growing as it'll be becoming red giant.
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Brian Cox visits the world's biggest vacuum chamber and performing experiment.
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If your program would predict crisis several weeks before crisis, and everybody would use your, or similar programs for prediction, crisis would happen in the same moment at which program predicted crisis, as everybody would start selling in the same moment..
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Can an antenna emit infra-red radiation or gamma rays?
Sensei replied to vitality00's topic in Modern and Theoretical Physics
You rather meant infra-red, as in title. Yes, you can emit infra-red photons from piece of metal through which we're passing current. No AC is needed, just DC. You should put metal with high resistance to vacuum (vacuum tube). With high enough voltage it will be emitting photons in visible spectrum (light bulb), at lower voltage black body emission will be shifted to invisible spectrum. But infra-red photons are easily absorbed. You can't transmit data similar way as using radiowaves for long distances (maybe in cosmic space). Do you have infra-red wireless mouse? Place hand between mouse and receiver, and it's no longer working. I have either radiowave wireless mouse and infra-red wireless mouse. Just checked - placed A4 thin piece of paper between IR mouse and receiver (5 cm distance between them). Mouse stopped working. Gamma rays from definition are emitted by radioactive/excited nucleus, or from annihilation of particle and its antiparticle. -
I was talking about ordinary people that witnessed by them self crime, something unnatural, something unexpectable. Not about believing people. Lie detector obviously won't work with somebody who was not original eye witness. That person didn't made up story, but heard from 3rd party source. I was replying to Moontanman comment about ordinary guy seeing something unnatural.
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That's interesting subject but completely off-topic. Whether lie detector will start complaining while examination about book/story that we know is not true? I don't think so. (until question "do you know it's not true?") We are just telling what we learned from the book/story. We didn't make this up. Just spreading knowledge get from that source. To make lie detector to work, we need to make lie by ourself. Somebody here have lie detector and willing to make experiment? Examine somebody asking for content of fictional book..
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Sorry, but reading book won't show anything.. You don't lie while reading any book. You're just reading somebody story.
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I will tell you story that happened month ago. Friend came by to me with newly bought IR camera for 3300 euros, with his new i5 @ 3 GHz laptop, complaining about that IR camera is not working as expected with 120 FPS. Instead it was something 5-10 FPS. I saw it on my own eyes, several hours. We installed IR camera software on my PC desktop i7 computer (supposed to be 10% slower than his laptop). and guess what. IR camera reached on my desktop the highest speed it could get... I literally see shock in his eyes.. I told guy 'you can buy from me mine PC desktop for 3k euros' That was initial proposition to solve his problems..
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Antiprotons are created during protons accelerated to relativistic velocities collide with rest protons. They can be held indefinitely in magnetic traps. [math]p^+ + p^+ \rightarrow p^+ + p^+ + p^- + p^+[/math] They have the same properties as normal protons, except charge that is -1e.
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That's why I think lie detector should be a common way to process what witnesses are saying.. People that ordinary lie, will immediately reject lie detector, sweating on thought of using it..
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There is also antimatter (antiprotons) created at CERN.. It doesn't automatically mean there is more energy produced in this process than it's used to make it happen..
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Deuterium isotope has 115 ppm, particles per million, abundance. That's it, you have to process ~39 tons of water to have 1 kg of Deuterium. You have to spend energy to separate isotope. Tritium isotope doesn't exist in nature in amounts needed for industry, and must be made..
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I am porting Windows VisualStudio C/C++ code couple times per month to Macintosh OS X XCode, and there is no way source code is compiling without problems.. f.e. XCode does not like 'static' in front of functions... static void func( void ) { } and you have error... Such code is telling compiler on Windows that func() is visible only from the same C/C++ source file, and nothing else, so func() might be reused in other source file.. Otherwise there is linker error " 1>test.obj : error LNK2005: "void __cdecl func(void)" (?func@@YAXXZ) already defined in main.obj" But it's subject for completely different thread..
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Gospels and New Testament cannot be used to prove or disprove existence of Jesus, similar like you cannot use The Lord Of The Rings book to prove or disprove existence of Gandalf. There is needed credible independent external source of information. And I find Tacitus and/or Suetonius books as such source. As long as they're compared to find their original state, verified age etc. using objective scientific methods without prejudices toward one or another option. Pontius Pilate was prefect of Judea between 26 AD to 36-37 AD. So there is very little time between 26 AD and 49 AD when they're mentioned to arrive Rome (23 years max, minimum 12 years) and apparently being quite active (otherwise they wouldn't be mentioned in Roman book).
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Antares/Cygnus- 6 seconds burn almost 2 billion USD
Sensei replied to Nicholas Kang's topic in Science News
Pretty much, yes. -
Antares/Cygnus- 6 seconds burn almost 2 billion USD
Sensei replied to Nicholas Kang's topic in Science News
You're picky. Tank of fuel is typically majority of space of rocket. Antares mass is 240 tons, while max load is 6 tons (2.5% of mass). Liquid Hydrogen has temperature between −259.16 °C to −252.879 °C. Below −259.16 °C, it's solid. Liquid Oxygen has temperature between −218.79 °C to −182.962 °C. (Other source says −222.65 °C to −182.96 °C) But I just read on wikipedia that Antares 1st stage rocket doesn't use Hydrogen, but kerosene. (plus Liquid Oxygen) http://en.wikipedia.org/wiki/Antares_(rocket) They're cold because of constant keeping them cool. Engines must have cooling down mechanisms, because burned fuel is heating it to high temperatures, much higher than metal melting point. It can be done by placing pipes coming from fuel tanks around engine. Liquid fuel is cooling it while flowing to inside of chamber. f.e. = for example. -
Antares/Cygnus- 6 seconds burn almost 2 billion USD
Sensei replied to Nicholas Kang's topic in Science News
Reason of failure will be under investigation by specialist that will analyze wreckage and data recorded by instruments. Rockets are huge tanks of liquid Oxygen and Hydrogen (so it must have < -250 C temperature), that are flowing through pipes to cool down engine chamber (to avoid meltdown), then to engine where they're starting joining to form water and releasing energy and it's flying through nozzle. There could be f.e. leakage of fuel in body of rocket, that uncontrolled started burning outside of engine chamber. -
switch() case code generated by C/C++ compiler can be much more efficient than above reduced quantity of if() code. Right-shifting instruction is like dividing by 2, but is also putting bit that's gone to Carry status register (at least on CPUs I worked). Pseudo-code that should be generated by compiler: value >>= 1; BCC case2 // Branch on Carry Clear [... code executed when the less significant bit is 1...] BRA end case2: [...code executed when the less significant bit is 0...] end: Now, repeat it as many times as there is significant bits in state variable. But jump-table for such switch is probably better option, like: state *= address of( second ) - address of( start ); JMP start+state start: BRA case1 second: BRA case2 (....repeat as many times as needed...) case1: [...code for case 1... ] BRA end case2: [...code for case 1... ] BRA end [....more cases...] end: size of BRA+parameter will be probably dividable by 2, so should be possible to be replaced multiplication by left-shifting of argument (state <<= 2)..
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Publius Cornelius Tacitus. Roman noble (not Christian) http://en.wikipedia.org/wiki/Tacitus described in his historic book Historiae (written in ~105 AD) about revenge of Nero taken on Christians for "burning Rome" in 64 AD. It's a matter to finding his original books from 105 AD, and examine them by scientific methods (radioactive isotope Carbon-14) to confirm their age (absolute required). Alternatively find as many as possible copies of books made later and comparison whether they're equal (or whether they were changed in the meantime). Books made before Constantine would be of course more credible (between 105 AD - 300 AD). Suppose so credibility of Tacitus books is confirmed by science: If Jesus was not a real man, who were Christians killed on the order of Nero? They made up Jesus? The same applies to Suetonius. http://en.wikipedia.org/wiki/Suetonius_on_Christians But he is the first time mentioning them existing in 49 AD (book written in 121 AD). Unlike Tacitus who had 8 years in 64 AD, Suetonius had to use older sources, as he born in 69 AD.
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Sorry, Strange, but they're not "idiots" but "victims of bad school education". I would start learning kids from showing them particles on their own eyes.. Devices such as Cloud Chamber, electron gun, discharge tubes, high voltage generators, lasers, polarization filters, diffraction granting, single/double slits, are cheap and quickly allow showing quantum world.. There is no reason why they're not in every primary school.
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What typical mobile phone application has? Menu. Program application where user can select something from menu. Few options, like Start, Best Scores, About, Exit. Move cursor between options, handling up and down keys. Press enter key - acceptance of selected menu item. Instead of making each menu item by hand, there can be created array of strings (or array of structures) with titles of menu item and f.e. call-backs executed when they're picked up by user - and you have usage for array.. To gain experience, you have to write programs. Write programs for yourself. Programs that you need. Ask mother, father, friends what application they would find useful. f.e. mother can tell that she needs note book for making list of things to shop.. What options have such app? Add new note, remove existing note, remove all notes, list all notes, searching, etc. etc.
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Difference between thermal radiation and radiation?
Sensei replied to vitality00's topic in Modern and Theoretical Physics
Agreement. -
Difference between thermal radiation and radiation?
Sensei replied to vitality00's topic in Modern and Theoretical Physics
I think you should go back to original sentence, that I was commenting: "I assume this thermal radiation arises because individual atoms are constantly being accelerated by their interactions." "constant acceleration" reminds me saying "releasing energy forever". But there is finite amount of energy in hotter object. IMHO thermal radiation arise because hotter object is appearing in colder environment. Acceleration of one molecule, and deceleration of other molecule is just method of transfer energy. Hotter object is sharing energy with colder environment, until both have equal temperature (in idealized closed system). We can place hotter object in vacuum, so there will be no direct interaction between it and colder environment, and the only way hotter object won't go to infinite temperature/infinite energy (which is obviously not possible) is to emit photons. Relatively cold hot object (in vacuum) will emit photons in infra red spectrum, warmer hot object will emit visible photons. Our normal environment also is emitting thermal radiation, but it's equal with all objects. -
Difference between thermal radiation and radiation?
Sensei replied to vitality00's topic in Modern and Theoretical Physics
Month ago I was test driving IR camera, were this was visible on 120 frames-per-second recorded movie (or real-time). Optris PI160 http://www.optris.com/thermal-imager-pi160 (3.3k euro with VAT) Software coming with IR camera were using Stefan-Boltzmann law to calculate temperature. I was picking up location using mouse on still frame, or animation, or in real-time (camera observing hot object, sending data through USB to computer), and it's showing what temperature has that spot of image. It is also showing graph, one axis temperature, second quantity/percentage of image. I will have camera probably in December. Now making list of experiments to perform. Of course it's not exactly "constantly being accelerated", because temperature of hot object is going down (as long as it's not heated from external source of energy). The more photons it emitted the closer temperature will be to temperature of environment, ~20 C for room temperature. Once average temperature of environment is reached, there is reached thermal equilibrium, object can't release more energy, because hotter air molecules will give it back (you can place 0 C water in front of camera and see how it's going up to room temperature, air molecules are accelerating water molecules, and cold water molecules are decelerating air molecules, so soon "blue" color on IR camera image is spreading around where was cold object, also on the ground touching it).