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Sensei

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Everything posted by Sensei

  1. Even you can turn light into matter and anti-matter.. It's called pair-production. You just need high enough energetic gamma photons. [math]\gamma + 1.022 MeV \rightarrow e^- + e^+[/math] On the left of equation there is 1.022 MeV, on the right of equation there is 2mec2 me = ~ 510998.928 eV/c^2 (rest-mass of electron/positron) and 2* 510998.928 eV/c^2 * c^2 = 1.022 MeV Electron is matter particle, positron is anti-matter particle. Positron is anti-particle of electron.
  2. Perfect yellow in RGB color model is 255,255,0 and in HSV/HSB it's 60,255,255 (Hue is in 0...360 range, Saturation/Value/Brightness in 0..255, but could be in 0...100%) Darker yellow on the left has HSV/HSB with ~50% Value/Brightness (RGB 127,127,0 in HSV/HSB 60,255,127). Couple times I was making color model converters from RGB <-> HSB/HSV in C/C++ ...
  3. Did you try this? https://en.wikipedia.org/wiki/Steak_tartare
  4. The main question should be whether you're comparing e.g. 200 g of rice vs 200 g of rice used to make rice Porridge (so total mass is ~ 800 g), or you're comparing 200 g rice vs 200 g of ready rice Porridge (which can have just 50 g of rice). According to rice Porridge recipe from the Internet there is needed 1:2:1 parts of rice/water/milk (some of it will vaporize) to make rice Porridge. (milk can contain fat influencing time needed to heat it) Rice in rice Porridge is just ~ 25% of total mass of ingredients.
  5. If "yellow" is mixture of green and red (like in CRT/LED screens), which just pretends only to human eyes it's yellow, you should say so since the beginning..
  6. Depends on cooking temperature, cooking technique and whether it should be rare, medium-rare or well-done. e.g. "Trichinella spiralis (...) occurring in rodents, pigs, horses, bears, and humans, and is responsible for the disease trichinosis. It is sometimes referred to as the "pork worm" due to it being typically encountered in undercooked pork products." https://en.wikipedia.org/wiki/Trichinella_spiralis "Cooking pork products to a minimum internal temperature of 160 °F (72 °C) will kill most species, and is the best way to ensure the meat is safe to eat." According to table of doneness here: https://en.wikipedia.org/wiki/Doneness only well-done and overcooked are exceeding recommended minimum internal temperature 72 C..
  7. IMHO "cat in the box" just shows inability to predict particle state until observation (it doesn't mean literal observation by naked eye!). Better word is measurement. As it can be made by any device. It's all about randomness at quantum level. When there is enough of particles (billions, trillions etc.), we can predict with some level of precision how system will behave at macroscopic level (therefor entire classical physics, which often lacks of randomness, which is causing philosophers to think about determinism, or even "greater plan" etc. etc.). Observation causes change of state of system, no matter if it's quantum system, or macroscopic system. When you're using Mercury thermometer to measure temperature of e.g. water, Mercury absorbs energy, and it's gone from object under observation (and never returns back!). Very tiny lose, nothing important at macroscopic level. Observation often means absorption of photons. Because you, or device, see event, these photons are gone from system under observation/measurement, and cannot be absorbed somewhere else, can't cause other event in the future anymore. The smaller system, quantum system, the larger influence of measurement has on the state of system. The more energy is absorbed from system.
  8. yellow is between 570–590 nm.. ps. Excuse me for being too pedantic..
  9. I use comments (in 99.9% of times) only to disable some part of code.. ps. And to-do e.g. // TODO: [...what to fix in the future...] Some IDE even have special feature to automatically search for and make a list of such TODO comments.
  10. Sensei

    mini-sun

    Star is doing fusion just because of pressure caused by outer layers of the star. If this pressure is not enough, you have just cloud of gas in cosmic space. Human made fusion reactors have to simulate this pressure using different methods than gravity. e.g. powerful superconducting electromagnets, and concentrated lasers are used to do it. But energy produced by fusion does not compensate energy required to cool down superconducting electromagnets and lasers, yet.
  11. Voltmeter (especially analogous) uses Ohm's law for measurement of voltage drop in test circuit. It has built-in resistor that has constant resistance e.g. 10 Mega Ohms (it should be even mentioned on the box, and on device). If you plug it in the middle of test circuit, it creates additional branch in circuit, and through it there is flowing very very little current (because of using ultra high resistance). Even if you want to measure voltage drop on e.g. diode, transistor or other semiconductor. How to convert electric current to human readable output? Pass current through electromagnet which is in the middle of permanent magnet. The larger current, the stronger electromagnet. It is free to spin in one, or two directions, and analogous needle can show force needed to move it on the scale.
  12. Nice try, Enthalpy. We have 1st April..
  13. I would use anything what is cheap, expendable.. Just in case it wouldn't survive return back to Earth in one piece.. How much can you potentially lose? $30-$50? But the temperature in the balloon does not increase, the temperature of the atmosphere decreases with the altitude. If someone opens aircraft door at a altitude 10 km, he/she will freeze at -60 C outside. At high enough altitude, balloon will freeze, gum will lose its properties, pressure inside of balloon is expanding it, and it'll crack, release Helium/Hydrogen gas, and it'll return back to the ground.. Better add to it cheap expendable smartphone with GPS (remove cover and everything what is useless for experiment, to reduce mass), to be able to find it after experiment using Google localization feature.
  14. Studiot, when the last time you were playing with LEDs (3mm or 5mm).. ? They have max recommended current 25mA...30mA.. And you want to give them 90...100 mA? With 9 V? e.g. https://www.sparkfun.com/products/9590 "1.8-2.2VDC forward drop Max current: 20mA Suggested using current: 16-18mA Luminous Intensity: 150-200mcd"
  15. If somebody lost civil rights, he/she can't vote, that's the whole "punishment" of losing civil rights, isn't? She had no idea that she lost civil rights, and cannot vote.
  16. If somebody lost voting rights, because of committing some crime, he/she certainly should not be on the list of voters. They made mistake to put her on the list, in the first place. Analogously, if somebody lost driver's license, it should be taken, and then it'll be easily identified because it's missing. Certainly, she should not be prosecuted just because somebody made mistake and included her on voter's list. Somebody might have no idea (or forget it) that lost civil rights.
  17. Cursor is usually changing shape when it hovers some element on the screen e.g. control, border of window etc. After hovering other area (move it), it should return to its normal shape. Cursor with shape "+" is used by e.g. Paint, and other 2D painting software like Photoshop. Cursor with shape "circle with a slash inside" means that control that is hovered is currently disabled and cannot be clicked/activated/used. However, in some rare situation, there can be error in application and cursor shape won't return to its normal shape. Also some lame hackers are changing shape of cursor, usually to nothing (hide it), to force user to restart computer. If you will leave computer with turned on network, they can use startup time to load/update when antivirus was not loaded yet. From your description, it'll unlikely. ps. Maybe it's result of ClickLock feature? Search Google for "how to enable/disable clicklock feature"..
  18. You're "victim of not proper education".. You claim that photon energy formula y [math]E=h v=\omega \hbar[/math] is incorrect.. But it used in many places in quantum physics. Starting from photoelectric effect: [math]h f - W = \frac{1}{2} m_e v^2[/math] Photon is disappearing from system, instead free electron is ejected from metal. And its kinetic energy (can be calculated from velocity) is reminder of energy needed to eject it. [math]v = \sqrt{ \frac{ 2 ( h f - W) }{ m_e} }[/math] C'mon! This can be proven simply using white light source, prism, and metal such as Cesium, Potassium, Sodium, Lithium.. Then annihilation, then pair production, etc. etc.
  19. You have opportunity to learn programming C/C++.. To install keylogger routine you need SetWindowsHookEx() https://msdn.microsoft.com/en-us/library/windows/desktop/ms644990(v=vs.85).aspx and it must be put in separate DLL (Windows XP+ requirement, in Win95 it could work without separate DLL). The most primitive rough version can be done within 10 minutes or so.
  20. You permanently ignore conversion of units.. and that's just for a start...
  21. Difference between Classical Physics kinetic energy [math]KE=\frac{1}{2} * m * v^2[/math] and Special Relativity [math]KE = m_0c^2\gamma - m_0c^2[/math] is only visible at significant velocities (at the moment unavailable for humans, except ions in particle accelerators), while approaching to speed of light in vacuum. Einstein with his 1st wife Mileva, work on Photoelectric effect, they used classical physics kinetic energy equation, not special relativity kinetic energy equation. ps. Probably nobody reading your posts, have any idea, what are you talking about generally.. ps2. You should never replace v by c in classical physics kinetic energy equation!
  22. Why not make scientific experiment.. ? Make keylogger which will store the all data entered by people who will receive it (friends/family?). Then after months of using, they will send you back results, stored words with errors and fixes. Then make parser which will find places where they made mistake (use database of English words).. But you would have to give them some way to filter out passwords and logins they use.
  23. 1) make more photos.. 10+... Various angles.. various distances. 2) make videos... move slowly during making them. 3) try different smartphone and/or regular camera to see whether effect is appearing with them or not. 4) does it appear in preview on screen? On photo there is visible paper box, and center of image in nearly at the corner of this box, and bars looks like interference pattern. On this video you can see how sound can affect water: https://www.youtube.com/watch?v=tI6S5CS-6JI
  24. Suppose so you have Uranium-235 atom. It has mass mu It's decaying to Thorium-231 and Helium-4, with rest-masses mth and mhe. U-235 -> Th-231 + He-4 + 4.68 MeV And it releases approximately 4.68 MeV energy (it's called decay energy). In this case (alpha decay) it (decay energy) is in kinetic energy of newly created particles. (small) part of that energy is taken by Thorium-231, and (larger) part of that energy is taken by highly accelerated Helium-4 nucleus. muc^2 = mthc^2 + mhec^2 + 4.68 MeV Reverse equation: muc^2 - ( mthc^2 + mhec^2 ) = 4.68 MeV Rest-mass of Uranium has been converted to kinetic energies of newly created particles. Rest-mass of Uranium, rest-mass of Thorium, and rest-mass of Helium can be measured independently many different ways. Decay energy can be calculated using above equation. Kinetic energy of newly created particles can be measured (they're (traces) visible by naked eye in e.g. Cloud Chamber). Kinetic energy in Special Relativity is [math]KE = m_0c^2\gamma - m_0c^2[/math] not what you wrote in title! ps. Multiplication by c^2 just coverts units from unit used to express mass to unit used to express energy. ps2. Why am I giving over and over again the same example of radioactive decay process? Because it's easy to see how rest-mass is converted to energy, without bothering much about original Einstein's work.
  25. My definition of "run" says that code should be executed.. https://en.wikipedia.org/wiki/Execution_(computing) "The term run is used almost synonymously. A related meaning of both "to run" and "to execute" refers to the specific action of a user starting (or launching or invoking) a program, as in "Please run the application." " When you would know everything, you would not be surprised to see how these two things are correlated..
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