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Sensei

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Everything posted by Sensei

  1. Not sure what you mean by "mutually exclusive" in the context of computer languages. But f.e. you can write Logo in C/C++/C#/Java/JavaScript/Net Framework etc. but you cannot write C/C++/C#/Java/JavaScript/Net Framework in Logo language.. Are not you mixing language with algorithm? In general purpose languages (majority of them, Logo excluded ) you can write pretty much the same algorithm, in their own version, with very little (subjective) changes. Have easier task for example than rubik's cube: binary search algorithm. And try making it in C, then in C++, then in Java, then in C#.. etc. In language that does not have object-orientated environment you can cheat by f.e. using call-backs, which will be emulation of virtual methods (C++ virtual method in reality is call-back internally). (in general solution to binary search algorithm it's needed for comparison of elements of unknown type at design time)
  2. Point like object has still coordinates x,y,z, at least in 3d. Point like object at rest looked from other point like object which is moving (or reverse), can look like line. Imagine you see point at x,y,z at time t+0, then 1 ns (nanosecond) later, it's at x+vx*10^-9,y+vy*10^-9,z+vz*10^-9 then after yet another 1ns it's at x+2*vx*10^-9,y+2*vy*10^-9,z+2*vz*10^-9 and so on. Where is it? If it's changing constantly its coordinates (or we (observer) are changing our, does not matter).. What does mean that object is point like? That our (observer) vx,vy,vz is equal to vx,vy,vz of that object (for instance two cars parallel on highway). That we and that point like object are in the same frame of reference. Can you give some black hole coordinate x,y,z? Yes. Can you calculate distance to some black hole from f.e. Earth? Yes. Can you calculate distance from some black hole to stars in it's neighborhood, or to galaxy center? Yes..
  3. I would rotate remote controller up-side-down, so buttons points down, and use normal tap water with used slightly humid toothbrush. After cleaning it up, put in on towel (without rotating), until drying. Water can't go inside against gravity. Remote controllers rubber buttons are often single piece of rubber, like this: Chance for getting water inside (especially if it's up-side-down) is pretty low.
  4. f.e. Pair production is process in which high energy photon, changes to matter and antimatter: [math]\gamma + 1.022 MeV \rightarrow e^- + e^+[/math] Electron and positron (electron's anti-particle) Photon must have more than 1.022 MeV = 1022000 eV energy. 1 eV is 1.602176565*10^-19 J It's 500 thousands more than visible spectrum green photon. After exceeding ~2 GeV energy there can be created proton and anti-proton: [math]\gamma + 1876.544 MeV \rightarrow p^+ + p^-[/math] (that's 1836.15 times more energy than above 1.022 MeV)
  5. Have you tried using zener diode parallel to circuit prior your current PCB? This will make sure no high voltage reach PCB. It will pass through zener branch. That does not sound like "power spike when the device is turned on"...
  6. That's not needed. I am uploading APK to my FTP. And in browser in mobile going to URL, and downloading APK. I was also sending APK in mail and worked fine. But better compress it to archive. Then on mobile decompress archive. And pick up APK in file browser, and it'll be installed. It's easy to write your own FTP on mobile. Then go to from computer connected in LAN even by local IP address. In v5.0+ in Information About Device > State > there is info what is its local LAN IP address of mobile phone. In my case it's 192.168.1.20 There is also MAC address. Lower signal means further distance (typically radio signal drops inverse square law), or there are obstacles. But on station, there is no serious obstacles for signal. Ah, If they are all at maximum, and you're on the station waiting for bus to go, these additional one are from other buses around you..
  7. Then watch the real particles in the real particle detectors, like in this video: http://www.scienceforums.net/topic/92471-the-limits-of-physics/#entry894800 Watch them by naked eye, not just numbers on white table, for more healthy approach.. f.e. alpha decay Isotope with nuclear spin=0, before decay has mass [math]m_{src}[/math], and is at rest, p=0. after decay newly made nucleus (with rest-mass [math]m_{dst}[/math]) has 2 protons less Z'=Z-2, has 2 neutrons less N'=N-2, and Baryon Number smaller 4 units, A'=A-4. Emitted alpha takes 2 protons, 2 neutrons. Decay energy (see my signature how to calculate it), is split accordingly to their masses. Energy prior decay is [math]E=m_{src}*c^2[/math] Energy after decay is the same, [math]E=m_{dst}*c^2*\gamma_1 + m_{alpha}*c^2*\gamma_2[/math] Momentum prior decay is 0. Momentums of new products is where you can show your math skills.. Are not they defined mathematically enough? Charge of particle -1e = -1.602176565*10^-19 C, or 0e = 0 C, or +1e = 1.602176565*10^-19 C, Kinetic energy of particle [math]m_0*c^2*\gamma-m_0*c^2\approx\frac{1}{2}*m_0*v^2[/math] for v<<c Rest-mass of particle measured by mass spectrometer. And observation how charged particle reacts for acceleration (more massive particle accelerates differently than lighter particle). And particle spin, measured in other device. ps. I think that students should go exactly reverse direction: experiments more than mathematics..
  8. Sodium bicarbonate + Acetic acid -> Sodium acetate + Carbon dioxide (gaseous) and water. Sodium bicarbonate is used to bake cakes (2nd name for it is baking soda). So it's available in any food supermarket. I am using it to bake pumpkin cake. Yes, they works, because they're ions while dissolved in water. But you will have plentiful of other reactions going on, if you won't use inert metal like Gold. f.e. Acetic acid + Copper Oxide/Hydroxide -> Copper acetate + water. You see by yourself, bluish color is probably Copper wire dissolved in water.
  9. Android or iOS? Typically WiFi are sorted by their strength of signal. Device most likely does not know what is their distance to router. Strong signal typically means very close router. (in the case of computer routers we can ping them, and measure time needed to receive reply from them, the closer they are the less time required to get reply) If you have Android device, and Android Studio installed, here is API for it. http://developer.android.com/reference/android/net/wifi/WifiManager.html public List<ScanResult> getScanResults () Return the results of the latest access point scan. Look at ScanResult definition: http://developer.android.com/reference/android/net/wifi/ScanResult.html As you can see there is no such thing like 'distance'. But if we scan at time t+0, and signal to some wifi is weak, and scan at time t+1, and it's stronger, and scan at time t+2, and it's full power, we were approaching router, the most likely. And reverse with dropping signal level with time.
  10. 333 mA is just maximum after exceeding it for too long time power supply will be damaged. What is the real current flowing through circuit, you should measure using the real ampere meter, plugged serial to your circuit, while it's running. Power supplies which can have many amperes cost plentiful of money. The cheapest thing you can do is using 230 V, 1-3 A rectifying diodes, 4 pieces, and make rectifying bridge. 1 A, 400 V max, rectifying diode cost $0.025 (yes, 2.5 cents), the last time I bought them. Even this smoothing capacitor is not needed. As electrolysis happens without it anyway. Transformer from 230 V -> 24V 5A, costs here $25 (250 times more expensive than above high voltage solution). Producing 25 mL of Hydrogen using 230 V takes 90 seconds, with Gold and tap water with salt addition. Producing 100 mL of Hydrogen using 230 V takes 90 minutes, with Gold and tap water without salt addition (less than 0.07 kWh energy used) The larger current, the more molecules are separated, and more Hydrogen produced. Whether there will be Oxygen on positive electrode, depends on what metal is used for it. I recommend Gold. 24 carat Gold, so rings 14 carats and 18 carats are not good enough and would be damaged permanently, as whatever 2nd alloy metal they have like Silver or Copper will dissolve. Water will be heated during electrolysis with such voltage. The worst est is electrolysis of water with Iron electrodes. Water temperature can reach 100 C. And current goes to 3 A (700 Watts). In this particular case, you need to watch it all the time. It won't be long maybe 20 minutes
  11. Unplug antenna, turn on TV, and listen 'music of Universe'...
  12. [math]A=\pi*r^2[/math] is area of base in m2 If you will multiply it by height: [math]V=\pi*r^2*h[/math] you will get volume in m3. Notice that you can have other shape as base, f.e. square [math]A=r^2[/math] Once it's multiplied by height you get: [math]V=r^2*h[/math] If h=r, it simplifies to: [math]V=r^3[/math] and you have volume of a box with all sides equal length.
  13. Ask him to repeat experiment inside of Cloud Chamber, so traces will be visible and record able by digital camera.. Then he should use electric field, or magnetic field to learn charge of emitted particles. This way he will know whether he has alpha, beta, or some neutral particle like gamma. Trace will be bend accordingly to charge, and mass of particle. He should use mass spectrometer on Gold foil to see whether he has Au-197. Before and after using on it alphas. Did he use 100% 24 carat Gold? If he used 14 carat (58.3% Au), or 18 carat (75%) Gold, it's contaminated by secondary metals like Silver, Copper etc. 24 carat can be little contaminated as well. He should use mass spectrometer on it anyway though. Hitting contamination by alpha could influence results. If mass spectrometer will tell him, it's contaminated with Silver, he should check how is behaving Silver foil instead of Gold foil. If contaminated by Copper, try Copper foil instead. Then melt Gold and Silver, or Gold and Copper, together, and make various foils with different percentages of both. And check them to see which one behaves like this original Gold foil. Whether these additional alphas are appearing more often while using alloy. Decay energy of Am-241 is 5.64 MeV. Part of it takes Np-237, but still it's quite a lot for alpha particle kinetic energy.
  14. But reaction is reverse.. MnO2 + 4 HCl → MnCl2 + 2 H2O + Cl2 Preparation page of https://en.wikipedia.org/wiki/Manganese%28II%29_chloride
  15. Hello! Have you seen "The Holy Quran Experiment".. ? https://www.youtube.com/watch?v=zEnWw_lH4tQ Best Regards!
  16. I prefer "how does photon interact with particles". Here you have summary of reactions: There is also absorption, and emission. https://en.wikipedia.org/wiki/Absorption_(electromagnetic_radiation) Fluorescence https://en.wikipedia.org/wiki/Fluorescence Luminescence https://en.wikipedia.org/wiki/Luminescence Not science questions..
  17. Learning is usually done by asking questions, and listening answers, and asking further questions to extend knowledge.. I don't see it in your posts..
  18. Take any sample editing software. They can learn you how to generate sample, instrument, sound that's pleasant to ears. Each sample is volume (amplitude) at certain time. Currently stored in 16 bit signed integer, -32768... +32767 range. Or unsigned integer from 0..+65535, If sampling frequency is 44100 Hz, each sample is send to speaker every 1/44100 s=22.675 us. Speaker is set to given amplitude-volume by electromagnets passing higher or lower or none current or reversed current (repelling from magnet, or attracting to magnet). If same sample like 65535 is send to speaker for some time, it has constant current flowing through electromagnet, and remain steady not moving in one state, and there is no sound, even though volume is at max. To generate sound there is needed to move it all the time. Back and forth. It pushes air around speaker. And it propagates further in air around device. Programming approach: take sinusoid wave, square wave. sawtooth wave, or other input signal (better repeatable). output from it multiply by some value. It'll be amplitude of sound. Change linearly amplitude in time from 0 to max, and sinusoid wave is going from 0 (no sound) to its maximum. Then decay, then sustain stage (no significant change of volume). Then release, drop volume in time to 0, Initial sinusoid (or other) wave will be modulated. And it's ADSR (Attack,Decay,Sustain,Release) model of generating samples/instruments/sounds. https://en.wikipedia.org/wiki/Synthesizer#ADSR_envelope Noise, contrary to music, is random. People call 'noise' music like techno,trance,metal, music they don't like, to discredit them. But they are not noise. They are not random.
  19. What a gibberish.. Increase of amount of money on your account, is scalar: money = money + income Decrease of amount of money also is scalar: money = money - expenditure Amount of money does not have 2nd dimension. Basically you don't know what is scalar and what is vector. Do you know how to convert vector to scalar? [math]length=\sqrt{dx^2+dy^2}[/math] for 2 dimensions. [math]length=\sqrt{dx^2+dy^2+dz^2}[/math] for 3 dimensions. it can be extended to further dimensions as many as we need. dx,dy,dz is relative between value at one time, and at other time, [math]dx = x1-x0[/math] [math]dy = y1-y0[/math] [math]dz = z1-z0[/math] so [math]length=\sqrt{(x1-x0)^2+(y1-y0)^2}[/math] for 2 dimensions. [math]length=\sqrt{(x1-x0)^2+(y1-y0)^2+(z1-z0)^2}[/math] for 3 dimensions. etc. for further dimensions. You cannot convert from scalar to vector back. You lost informations while conversion. If we will have x(t),y(t),z(t) functions, You can make function f(t) like: [math]f(t)=\sqrt{(x(t+1)-x(t))^2+(y(t+1)-y(t))^2}[/math] for 2 dimensions. [math]f(t)=\sqrt{(x(t+1)-x(t))^2+(y(t+1)-y(t))^2+(z(t+1)-z(t))^2}[/math] for 3 dimensions. and convert entire data from 2d to scalar. or from 3d to scalar. f.e. take location from GPS of your smartphone/car, take time from clock, store them in database record, repeat all day long. Path can be drawn on the map in future. It's full of detail. Then after processing database with above function will be showing distance that you traveled, in 1 second steps. Without info about where you were. Some data has been lost during conversion. If you will sum the all scalars, you will have total distance traveled during entire recording. If you divide distance traveled by time, there will be average speed (scalar). Again local fluctuations of speed will be lost. Less data in scalar than vector (locations), but sometimes still useful for certain things.
  20. As long as mistakes are quite insignificant. Huge mistake ends up in death. And inability to spread gens for further generations. Take for example motorcycle riders, and base jumpers.. If somebody is addicted to adrenaline (or does not feel natural fear, or have issues with predicting future of his/her actions etc.) because of mutation in genes, might not survive to spread this mutation further. Intelligent people learn on other people mistakes. Even after their death. Nonsense.. Original version of it, is about inability to predict whether unstable particle will decay or not, and when it will happen. It's about randomness in quantum world. Later with additional (unnecessarily) introduction of consciousness (making it even less scientific). Device measuring decays f.e. does not have any consciousness..
  21. Mac OS X have xCode. https://developer.apple.com/xcode/
  22. Try for example Zinc Hydroxide and Acetic Acid. Zinc Hydroxide is white, Zinc Acetate is colorless. Other example is black Copper Oxide CuO, after reaction it often change to blue compound.
  23. You're talking about hypothetical quantization of space, and quantization of time. You should therefor get familiar with Planck units, such as Planck length and Planck time. https://en.wikipedia.org/wiki/Planck_length https://en.wikipedia.org/wiki/Planck_time As you can see they're billions times smaller than anything we are able to measure currently.
  24. They are electrons from beta decay minus of radioactive isotope nucleus. and they can be electrons from decay of f.e. muon-, pion-, pion0, secondary cosmic rays, that were created from primary cosmic rays. https://en.wikipedia.org/wiki/Cosmic_ray
  25. Electron, or other charged particle, with high kinetic energy, while passing through medium is ionizing medium (and decelerating), and further electrons of medium are ejected and accelerated. This is how trace in f.e. Cloud Chamber is created. And can be seen by naked eye. Long thin trace is from electron, short bold trace is from alpha particle. Here you have instruction how to build Cloud Chamber by yourself. It's cost $30-$50 while using dry ice. But you need to have 1 kg (here they don't sell smaller amount) each time you want to run it. Electronic cooled versions (Peltier cooler) is much harder and more expensive to build. But more convenient to use. Bubble chambers are using liquid gas near 0 K temperature. f.e. liquid hydrogen below 33 K. https://en.wikipedia.org/wiki/Bubble_chamber Difference is in used medium. Further development of particle detectors: https://en.wikipedia.org/wiki/Particle_detector Other device you might be interested in is mass spectrometer. It's separating particles depending on their masses. f.e. split atoms of same element to their isotopes, each one to separate container for further experiments. https://en.wikipedia.org/wiki/Mass_spectrometry
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