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Sensei

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Everything posted by Sensei

  1. Pigeons with attached camera during flight revealed that they don't fly straight line to target. They're using well known by them objects on the ground such as roads, rivers, train tracks, mountains as guides to where they want to travel. Making path much much longer than optimal straight line. It was visible even in Top Gear episode (Series 4, Episode 4) where James Mays and Clarkson tried to beat pigeons (some of them had attached camera, so it was visible how they are flying). Search for it on YT. http://en.wikipedia.org/wiki/Top_Gear_%28series_4%29 "Time Challenge: Can a Ford SportKa, equipped with the world's most advanced (and expensive, at ?2500) satellite navigation system beat a flock of racing pigeons? May forgot to use the postcode search and wasted 25 minutes to reach the right address, having originally arrived at an identically named road in the wrong suburb. Regardless, the fastest pigeon won with 30 minutes to spare even after discounting May's mistake, with thirteen others arriving in-between. Clarkson called the SportKa way, way better than a Citroën C2, and ridicules May for losing."
  2. If nanobots would self replicate it sounds like the end of human kind.. Viruses don't self replicate. They introduce their DNA to living cell, and cell is turned to be virus factory. To reproduce there is needed source of energy and matter that will be used to building thing. Nanorobots currently don't exist. You cannot control such small device with radiowaves.
  3. Swansont was talking about Pu-238 , Half-life 87.7 years http://en.wikipedia.org/wiki/Plutonium-238 "Plutonium-238 is a very powerful alpha emitter and – unlike other isotopes of plutonium – it does not emit significant amounts of other, more penetrating and thus more problematic radiation. This makes the plutonium-238 isotope suitable for usage in radioisotope thermoelectric generators (RTGs) and radioisotope heater units – one gram of plutonium-238 generates approximately 0.5 watts of thermal power." "This same RTG power technology has been used in spacecraft such as Voyager 1 and 2, Cassini–Huygens and New Horizons, and in other devices, such as the Mars Science Laboratory, for long-term nuclear power generation." Pu-238 is a good test for verification of mine previous calculations of decays per second in post #3. 87.7 y half-life = 2,767,601,520 seconds 1 gram of Pu-238 = 6.022141e+23 / 238.049553 = 2529784628497080000000 atoms. Enter that in OpenOffice SpreadSheet Initial Quantity and Half-Life, and we're receiving decays per second = 633,585,795,072 Each decay is releasing 5.593 MeV, which is 8.959986e-013 Joules. 8.959986e-013 * 633,585,795,072 = 0.5676919854 Joules per second (article mentioned 0.5 Watts) Pretty close.
  4. Uranium-238 has Decay Energy 4.27 MeV 4.27 MeV is 6.84*10^-13 J To heat 1 gram of water for 1 C you need 4.1855 J of energy. 4.1855 J / 6.84*10^-13 J = 6.12*10^12 atoms of Uranium-238 would need to decay to detect increase of temperature of 1g water for 1 C. That amount is 1/100,000 of 1/1,000,000 of mole. But U-238 is quite stable. Half-life is 1.41*10^17 seconds (nearly 4.5 billion years). If you have 1 kg of pure U-238 now, you will have 500 grams of U-238 after 4.5 billion years (and other products of decay), and 250 grams after 9 billion years. Some time ago, I have made application for calculating quantity of decays per second: Unpack ZIP, and load it to OpenOffice, and enter in the second row Initial Quantity of unstable atoms and Half-Life in seconds. They will be spread to the all below rows. And show decays per second and graph. Unfortunately 1.41*10^17 seconds is too much for OpenOffice to handle it (math issue of application). But in second example I used 1.41*10^14 seconds (1/1000 less) (=~4.5 million years half-life) and 1 mole of Initial Quantity (6.022141*10^23). Result shows that there is approximately ~3 billions per second decays. So for 4.5 billion years half-life there will be ~3 millions per second decays. You would need to wait nearly 576 hours to heat 1 g of water for 1 C if you would have 238 grams of Uranium-238. Energy in the core of Earth has nowhere to go, so it will add up. Half life calculations.zip
  5. That looks like similar issue to yours: http://stackoverflow.com/questions/8011692/valueerror-in-decoding-json http://stackoverflow.com/questions/16018780/decoding-json-with-python
  6. These paths are Windows-like. Server is Windows? I don't think so.. They're rather Linux-based..
  7. If you have code: if( x > y ) { z = x * a; } else { z = x * b } You can replace it by f.e. z = ( x > y ) ? ( x * a ) : ( x * b ); or simpler z = x * ( ( x > y ) ? a : b ); Comparison operators > or < can be replaced by subtraction (they're subtraction in fact in CPU, but result is forgotten and remaining is only CPU flag register). So, ( x > y ) can be replaced by a=x-y; and then you have to check whether a is positive or negative value, or equal 0 (x is equal y). If value is negative sgn() or sign() function will return -1. If value is positive sgn() or sign() function will return +1. If value is 0, it'll return 0. So, if( x > y ) can be replaced by: sgn( x - y ) max( x,0 ) will return 1 only when x is equal 1. max( -x, 0 ) will return 1 only when x is equal -1. (assuming x is result of sgn()) So whole equation should looks like: ( max( sgn( x - y ), 0 ) * ( x * 100 ) ) + ( max( -sgn( x - y ), 0 ) * ( x * 50 ) ) which should be equivalent to if( x > y ) z = x * 100; else if( x < y ) z = x * 50; I hope so I inspired you a bit.
  8. Result of plasma shot is destruction or damaging of thing that you shot, not "exerting a force" like it would be some kind of slowly moving ball... On website's movies where you found above screen-shots you can see how they damaged target. Space shuttles and space station look like Swiss cheese (under microscope) due to constant hitting them by protons accelerated to relativistic speeds from the Sun and other stars. Holes have diameter of single atom or so. Imagine you have piece of metal/iron, and turn on powerful electromagnet above it. Metal "jumps" attracted to electromagnet. So imagine couple electromagnets in row, one more powerful than the other. And they are switching in right order, precisely synchronized. When previous stops working, next one in queue is starting attracting... Difference between particle accelerators and plasma railgun is just in details (like using vacuum in accelerators (which limits loses of energy), large size, and circular path). Positive electrode of DC circuit attracts electrons. Electron escape atom, and goes to circuit. Then atom that's near first ionized atom gives its electron to previously ionized. And it goes and goes through medium. Electrons starts flowing through path made by positively charged atoms. Negative electrode of circuit has excess of electrons (they are residing inside of capacitors) and gives them to ionized atoms. At 10-12 kV of DC made by CW generator I can see how it SLOWLY happens. It builds up a few seconds. It's the best view in darkness. Violet photons are emitted by thin a few cm length thunderbolts. http://en.wikipedia.org/wiki/Corona_discharge http://en.wikipedia.org/wiki/Electrical_discharge When these lines of ionized atoms from positive electrode join negative electrode, there is "explosion" and instant discharge of CW capacitors (and we see flash, loud voice, and sphere of plasma like in #3 post), and everything starts from beginning. Energy is charge in Coulombs * Voltage E=Q*U Q=I*t Q divided by e is quantity of electrons in this case. 1 C/1.602*10^-19 C = 6.25*10^18 electrons. If we have voltage like 6 kV it will make plasma when distance between electrodes is like 1-2 mm or so. If we will move them a bit further, nothing will happen. But when we will increase voltage to f.e. 12 kV, it will again start working. After further moving away, it's stopping working again. For really large distances there are needed millions of volts.
  9. You can see it on your own eyes, not just on photo, in cloud chamber.
  10. You should watch this video: Don't try to lost consciousness on street in cheap cloth (at least in France).
  11. Sensei

    solar energy

    Inverter should be after electricity meter.. When solar energy is produced, energy goes to inverter, and is used by electric devices. But when there is no sunny day, or night, obviously solar energy is unavailable, and used is energy from power station. If you're outside of home whole day, and returning at night, obviously you're mostly using power station energy, not solar energy. There is needed storage for solar energy, so whole sunny day it'll be loaded, and then used at night.
  12. How to create antiprotons is described in this article http://galileo.phys.virginia.edu/classes/252/particle_creation.html Protons must be accelerated to v>0.99c.
  13. And wearing Karategi/Kimono makes you almost Bruce Lee.. One of mine favorite:
  14. CW generator doesn't work with DC at all. It requires AC, AFAIK. I have tried with 240 VDC, and it simply didn't load at all. You can, or if you're using ceramic capacitors even have to, first convert 240 VAC to DC, then make your own AC from DC with required by device higher frequency than 50 Hz. And then multiply voltage by CW to really high. A lot depends on pressure of gas. Krypton is inside of hermetic tube. It can have pretty low pressure. Checking it would require destroying device. I don't have experience with rail guns nor plasma guns (who on this forum has? ) But I think you mixed two things. (typical) electromagnet requires DC (with pretty low voltage, it's after all just wire with low resistance). And the higher current you will provide to electromagnet (or just wire), the higher magnetic field you will receive surrounding them. If you will swap direction, you will change electromagnet from attracting to repelling. But 50 Hz constantly switching back and forth directions will be probably completely useless for railgun (that's typical transformer). You want attract projectile once, then repel and done. When first stage is repelling, second stage has to be attracting with even more power, so projectile is accelerated in that direction. AC for CW generator is another circuit, independent from electromagnets. CW current is always DC on output. It's purpose to ionize, and nothing more. You don't use such high voltage to power electromagnets (it would be senseless and most probably would blow up wires and/or capacitors). In electron gun, indeed such high voltage is used to attract electrons. And they fly through hole in anode. Real magnets are disallowing them to join with anode, and then they continue flying further in vacuum.
  15. There are generally two. I can switch between them, by just reconnecting wires. (mine has more than 70 stages)
  16. No. It's very small red spot. So small you probably wouldn't see it if I would make photo (something like 1-2 mm). Mine point was- you cannot change color of plasma.
  17. Vacuum would definitely increase distance plasma is traveling Electron gun requires vacuum. It will be ionized. After all it's helium, neon, argon, xenon, etc. gas. That's how these elements were discovered - by spectral lines present in air spectrum. Scientists compared air spectrum (from discharge tube) with pure nitrogen and pure oxygen spectrum (from electrolysis or chemical reactions producing them) and noticed difference between them. Yes, of course. One mine colleague touched it when it was loaded 3 kV and since that moment he doesn't touch anything in lab anymore without asking.. You could smell of burning flesh (literally).. I touched CW generator electrodes with 6 kV accidentally once too. Somebody called me, in the middle of experiment, and I forgot to discharge capacitors entirely. When I returned, touched it and fall it.. Mine hand shake after several hours after that. I had to use something that is not metal. It's 1mm thick cardboard. If we will place it between two electrodes with 25 kV, and wait couple seconds (double or triple as long as without cardboard between them) electric arc will be very powerful and will cut cardboard making pretty big hole in it. There is no glass, there is nothing surrounding it. When you will take glass tube/pipe, attach electrodes from both sides and seal ends, and fill by some gas (hydrogen, oxygen, chlorine, I have created from electrolysis, CO2 from dry ice, air), optionally lower pressure, you will have self made discharge tube. Pretty close. They are standard wires for connecting breadboards. Mine cascade generators are on breadboards, so I can freely connect/disconnect them together. Although I saw on the net people are taking transparent kitchen plastic boxes like this one making 4 holes, attaching banana connectors to it from both sides, and putting capacitor bank inside, filling by mineral oil, and sealing them permanently. But if some capacitor will blow up, you have problem how to fix it. Free nucleus is attracting free (or not) electron. Electron is emitting photon, or multiple photons with various frequencies, and is attracted more and more by nucleus. And these photons is what we see as color of plasma. With graphite electrodes I had red sparks.
  18. Increasing core quantity is cheap and easy way to increase power of processor without bothering with smaller scale elements etc. We certainly (and thankfully) didn't hit the limit of how small transistors and elements can be, yet. Graphics cards are now coming with 2880 cores btw. http://www.nvidia.co.uk/object/graphics_cards_buy_now_uk.html CPU can go GFX card route too. But it should be done by changing architecture permanently, and limiting instruction set (which is quite obsolete, basing on Intel 8086 from 1978), which will simplify making core. So there will be possible to pack them together in larger quantity tightly. This would make all currently Intel compiled software obsolete, so industry is trying to avoid it as long as they can.
  19. 6 kV is not very high. I have Cockcroft-Walton generator producing ~40 kV (and expanding its capabilities with time). It's used in experiments with x-rays in cloud chambers. To fully load you need couple seconds (by 240 VAC @ 50 Hz). At least with electrolytic capacitors (which have pretty high capacitance). These are screen-shots from video with ~25 kV setup. I have videos showing difference between 6 kV, 10 kV, 25 kV, 40 kV setups. I can send you videos privately if you're interested. (whole "explosion" takes less than 1 frame of recording it camera, so sometimes there are misses, recorded just voice without actually picture. I will need to get high speed camera some day..) That sounds to me that you want to accelerate plasma using quickly changing magnetic field in barrel. Is that right? Plasma is highly reactive. It will steal electrons from surrounding it matter, and unpredicted chemical reactions will happen. Production of ozone is very high with mine above setup (especially with continuous coronal discharge when we will prevent "explosion"). You feel like after summer thunderstorm in seconds.
  20. Shape of physical object changes depending who is watching it, and distance to object. Distant galaxy seen by naked eye or cheap telescope looks like spherical blob. Metal plate, or wall, looks flat to us, but after large zooming by microscope they will reveal to be mountain-like irregular. So, observed shape is or might be just an illusion, depending on capabilities of observer or device and/or distance. Just a thought irrelevant to whole discussion. ps. I have no idea why it was moved to Philosophy..
  21. For Earth's scale objects typical method is sending photons to object and after reflection, detecting returning signal delay (t=2*d/c) It's used in radars, using radio waves. But if you attach mirror to object, or retroreflector (like on Moon), you can use normal visible range photons. For our solar system and galaxy scale distant objects we can use knowledge about position of Earth around Sun and Pythagoras triangle. At one day of year Earth is closer to some star or planet, at other day of year Earth is farthest from it. You can deduct that tangent alpha is equal to ~1 au (=~150 mln km) divided by distance to measured object (from Sun). I have made picture for you to visualize:
  22. That's not an issue. That's normal. You misunderstood idea described in article. It's meant to be storage facility, not regular power station. Energy is produced elsewhere, and solar panels and windmills are example power stations that are periodically working. Once they lost energy source (at night, or when there is no wind), energy is restored from storage and customer continuously receive energy. I stay doubtful. How did you calculate that your idea will be 95% efficient?
  23. Each light year is approximately 299792.458 * 60 * 60 * 24 * 365.25 = 9.46*10^12 km 53.0 million light years * 9.46*10^12 = 5*10^20 km distance between us. 3.2 mln km/h = 888.9 km/s 5*10^20 km / 888.9 km/s = 5.641*10^17 seconds That's 1.78*10^10 years. 17.8 billion years. Not millions. Article is wrong by factor 1000. Not first and not last time journalist shows his inability to calculate. "First of all, even at its current speed, it will take more than 17.5 million years to get here."
  24. We have protons at rest. Accelerating part of them to v > 0.99c and hitting them to other protons at rest. Result is production of protons and anti-protons: p+ + p+ -> p+ + p+ + p+ + p- Like this has been showed in this article at the bottom: http://galileo.phys.virginia.edu/classes/252/particle_creation.html And from frame-dependent kinetic energy of particle, two new real particles appeared..
  25. Start > Run.. regedit Then search for HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run And add new key. With value path to executable. Or rundll32.exe [dll name] [function name] if it's linkable library (or Windows service - this one can be controlled by administration service panel). The most of mine Windows applications have option to run them with Windows, minimized, and in tray icon. I like to have them at hand.
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