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Everything posted by Pantaz

  1. Electric motors produce maximum torque at zero rpm.
  2. Please, take a few minutes and read Lizzie Velasquez's story: http://www.bbc.com/news/blogs-ouch-30948179 Excerpt: "She was 17 when she stumbled across a YouTube video entitled "The World's Ugliest Woman"."
  3. At 14 years old, using mostly scrap materials, William Kamkwamba built a wind turbine to power his family's home.
  4. Throughout your term of employment you retain the right to choose to work there. A slave has no such choice.
  5. Start here: http://www.backyardmetalcasting.com/index.html
  6. There is a wide variety of GPS modules and devices available for DIYers. Take a look at Hack-a-Day for some ideas. Some retailers: https://www.sparkfun.com/search/results?term=gps&what=products http://www.seeedstudio.com/depot/index.php?main_page=advanced_search_result&search_in_description=0&keyword=gps
  7. Actually, "bevel up" planes work very well. http://www.google.com/search?q=bevel-up+plane
  8. You might start by looking at what's in existing products -- Lacquer Thinner MSDS
  9. Yes, but your question is ambiguous. Hydraulic systems can use delay valves, so I guess you could consider that a "device" for imparting hysteresis. (Undesired hysteresis is actually a common problem in hydraulics.) Mechanical systems would have it built into the design of the mechanism.
  10. Some well written definitions: http://www.webopedia.com/TERM/O/operating_system.html http://en.wikipedia.org/wiki/Operating_system http://www.webopedia.com/TERM/N/network.html http://en.wikipedia.org/wiki/Computer_network
  11. Many people here will be quite happy to help if you show that you are at least trying to do your own work, but do not expect to be spoon-fed answers to your homework.
  12. Let me see if I can simplify this, from the perspective of someone with no formal scientific education. Fred, using Newtonian physics, calculates the impact force of an apple striking the ground after falling from a tree. Jack measures various parameters of an actual apple, falling from an actual tree. He records the results from dozens of apples. Lisa compares Fred's math with Jack's measurements. The data sets match within acceptable margins of error. (For example, calibration factors within the measurement instrumentation; wind causing some of the apples to fall in a slightly different trajectory.) Conclusion: The theory behind Newton's laws, for the purposes of apples falling from trees here on Earth, is demonstrated to be valid. For an alternate hypothesis/theory to be accepted, it must also be able to mathematically predict similar results for those same apples falling from those same trees. If the new hypothesis can not correctly make these predictions, then how can you trust it to be accurate about anything else?
  13. Modern automatic transmissions are highly integrated into the vehicle's electronics.
  14. I believe there are some deep-dwelling ocean creatures with rudimentary light-sensing organs.
  15. Is the class, "Introduction to Programming", or "Introduction to Programming C#"? If you have no previous coding experience, then you should be learning about basic principals of programming and machine architecture.
  16. Pantaz


    1. Stick a piece of tape over the face of the magnet. After retrieving the metal disk, pull off the tape, and the disk will fall away. -- OR -- 2. Buy or build something like this: http://toolmonger.com/2009/08/26/wave-your-magwand-and-swarf-disappears/
  17. From an article at news.discovery.com: "The Maya recorded time in a series of cycles, including 400-year chunks called baktuns. It's these baktuns that have led to rumors of an end-of-the-world catastrophe on Dec. 21, 2012 -- on that date, a cycle of 13 baktuns will be complete. But the idea that this means the end of the world is a misconception, Stuart said. In fact, Maya experts have known for a long time that the calendar doesn't end after the 13th baktun. It simply begins a new cycle. And the calendar encompasses much larger units than the baktun."
  18. Note to Panopticon: It's generally considered bad form to post a file link without some description of what it contains. I spent a few minutes back-tracing the source of the PDF -- http://www.sede.enea.it/produzione_scientifica/WebTechnology.html On that page is the link, titled: "Excess of Power in Deuterium-charged Palladium - Jan 2009 - Vittorio Violante" (The website is in Italian, but this and a few other links are in English.) The English-language document is just a four page "technology brief" that discusses ongoing (as of Jan 2009) work building upon Fleishmann & Pons fusion experiments.
  19. Everything you need to know about $cientology... http://www.xenu.net/
  20. I would consider "skool" a misspelling, rather than a comparative word. For many words, you must also consider usage. Using your example: Main Entry: school Part of Speech: noun Definition: place, system for educating Synonyms: academy, alma mater, blackboard, college, department, discipline, establishment, faculty, hall, halls of ivy, institute, institution, schoolhouse, seminary, university Part of Speech: noun Definition: body of philosophy on subject Synonyms: belief, creed, faith, outlook, persuasion, school of thought, stamp, way, way of life Part of Speech: verb Definition: teach Synonyms: advance, coach, control, cultivate, direct, discipline, drill, educate, guide, indoctrinate, inform, instruct, lead, manage, prepare, prime, show, train, tutor, verse - Source: Thesaurus.com
  21. Recommended reading: http://forums.randi.org/local_links.php?catid=18
  22. We used matched-pair angular contact ball bearings in superchargers spinning >35000 rpm. That was more than twenty years ago, and I don't have any of the engineering data, but I know the lateral shaft load was significant (using "multi-v" belt drive). When you get all of your data together, just call the technical department at one of the bearing manufacturers. They will help you determine the best solution.
  23. Many suppliers have a "bearing selector" page. Some are more detailed than others, so you might need to try a few different pages.
  24. The Wiki page covers it pretty extensively, including numerous citations: "The Earth's field has alternated between periods of normal polarity, in which the direction of the field was the same as the present direction, and reverse polarity, in which the field was the opposite. These periods are called chrons. The time spans of chrons are randomly distributed with most being between 0.1 and 1 million years with an average of 450,000 years. Most reversals are estimated to take between 1,000 and 10,000 years. The latest one, the Brunhes–Matuyama reversal, occurred 780,000 years ago. ..." http://en.wikipedia.org/wiki/Geomagnetic_reversal
  25. If you are responding to swansont's last post, he referred specifically to the "initial collapse" described in the NIST report. As previously posted, the NIST report states that a 2.25 second period of free fall occurred between two periods of "acceleration less than that of gravity": When you added "simultaneously" you have indeed proffered a false premise. The report specifically states the measured free fall occurred prior to contacting additional material. Certainly, some portions of nearly any collapsing structure will experience brief periods of "free fall" between the instances of contacting/impacting neighboring debris. The initial 1.75 seconds were determined to be less than gravitational acceleration. Per your analogy, you would fall 15 meters before your twin achieved "free fall". Bear in mind, at that 1.75 second mark, you have reached a velocity of 17.15 meters per second (and continuing to accelerate), but your twin has been accelerating more slowly, so he has fallen a lesser distance and is traveling at something less than 17 m/s. Your velocity will never match that of your twin at any given time after zero. As a (very rough) example, let's imagine that your twin's initial acceleration is 8 m/s^2 (free fall being 9.8 m/s^2). At 1.75 seconds, he has fallen only 12.25 meters (2.75 meters less than you) and is traveling at only 14 meters per second. (Note: I understand that the initial 1.75 seconds is a period of increasing acceleration for the twin, so the velocity and distance traveled will be somewhat greater than my example, but I don't know how to do the calculations.)
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