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Externet

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Everything posted by Externet

  1. Thanks. Well, then, a kick-ass 500 W+ strobe lensed downwards, for a flash every 5? seconds when orbiting on the dark hemisphere. Or whatever is feasible. Being NASA, ESA and the Russians, provide more doorways for the proposal. Someone here should have or know a connection... I hope. Edited-added: Am willing to pay for one on this price range----> http://www.ebay.com/itm/500W-Studio-Lighting-Flash-Strobe-Kit-Photography-Light-Brand-New-/380712907314 (I do not believe the "free shipping" part to up there ) Am sure cannot afford the installation fees nor let me do it myself ... Does the orbiting ISS faces always the same surface towards earth; or will it requiere a gyroscope mount ?
  2. Correct, there is methods to locate the ISS for all having a computer.
  3. Would it be possible for some of the well connected SFN members to propose NASA the implementation of a strobe light beacon on the International Space Station in such a way to project a cone of perhaps 20 degree colored strobing light downwards as to tell the world its presence overhead during night passes ? It would be very significant, on an insignificant power consumption and perhaps cost, or a harmless green pulsed laser instead. I suggest such as the ISS is discernible to naked eyes with good vision. A light coming from it should be highly discernible too. Would that harm any technological issues?, for the ISS just to tell us, the world... "We are over your head now!" "We are an IFO !"
  4. It would be soooo nice if SFN big shots could propose NASA to implement a colored strobe light on the International Space Station, aiming a discernible light vertically downwards during the nighttime passes, (with some cone of projection, perhaps 20 degree) Or even a harmless green laser pulsing... Would that harm any technological issues?, for the ISS just to tell us, the world... "We are over your head now!" "We are an IFO !" I propose such as the ISS is perfectly discernible to naked eyes with good vision. A light coming from it should be highly discernible too. Sorry if this is hijacking, ----> delete this post; I would start the subject on a new thread. Edited: Now opened as new topic ----> http://www.scienceforums.net/topic/78493-sfn-to-nasa-proposal/
  5. Found that most people often dream about being chased, with physical difficulty to run away or escape from the chase but never getting caught. This is not about the meaning of such or especulate an explanation; but the common scenario to many. How many unrelated different personalities and personal life intricacies can experience such common dream ! ----> Do you get that one too ?
  6. Brainstorm to develop an instrument to measure the propagation speed of gravity.
  7. Has any solar sail/motor type of device has ever been built and worked on earth, experimentally ? Sort of a Crooke's radiometer, with the radiation-pushed half of a spinning sail exposed to sunlight and the returning half shaded, all perhaps in high vacuum ? If half the globe of a Crooke's radiometer is shaded, would such be an equivalent of a solar sail motor ?
  8. Thanks. Of course, it is high frequency AC; but AC fed solenoids/relays/electromagnets do sustain attraction when energized. I would have to try myself if nobody else on the forum uses such cooktop. Seems 340 alloy is the convenient one.
  9. Seen advertisements where the ferromagnetic cookware used on induction cooktops turns the cooktop power off when pulled away from the 'burner' by some built-in sensor. Am fine with that. If the energy is magnetically transferred to a ferromagnetic pot; how can the pot be effortlessly lifted without the attraction force impeding the action ? How does it work ? Question 2 : What stainless steel alloy is more convenient for induction cookware that will be used suspended 3 mm above the induction cooktop suface ?
  10. From experience, it is a product that perfoms. If its price is justified, depends on your application you did not expose. Sheets of different dimensions show at ----> http://www.ebay.com/bhp/sorbothane-sheet ; but you never mentioned size you want. Plain consumer insoles of gel or sorbothane seem more expensive than sheets. Shock "resistant" and shock absorbent are different animals, and simple to do a test, with the materials you mention, or a sandwich of those fancy gels. A plain lead bar can do wonders too.
  11. Search for sorbothane products. Their main site has some and applications too.
  12. They sleep because are fed by people. They do not have to look/hunt for food by themselves. They practice symbiotic psicology for comfort with humans. Try not feeding for a while and will start climbing the walls to eat a bug...
  13. Hi. This travel check list works very well for me all times. Improve it, add your items, delete what you like; print copies and should serve you well in the future. Just keep it where can be found when needed ============================================================ TRAVEL CHECK LIST ===Personal items: Comb, brush Cosmetics Dental care items Deodorant First aid supplies Glasses, lenses, cleaning supplies Hair dryer Hand, moisture lotions Insect repellent Medicines, vitamins Nail clipper Cologne, perfume Pocket knife, tools Prescription duplicates Cotton swabs, balls Razor, shaving cream Reading glasses Shampoo Sunglasses Sunscreen lotion ===Documents: Adresses Stamps Cheque book Credit, ATM cards Foreign currency Health card Insurance International driver permit Itinerary Passport, visa Pen, paper Telephone card Telephone numbers Picture identification Driver license Reading material Reservations Tickets Tour books Traveler cheques Vaccination certificates Wallet Work folders, documents ===Before leaving: Advise family of itinerary Advise police Advise neighbors to watch house Arrange lodging for pets Clear and set refrigerator Advise postal office to hold mail Leave keys at safe place Lock windows, doors, garage, attic, basement Mow grass Store jewelry, guns, valuables at safe place Set heat, airconditioning Set timers and lights Shut-off water supply mains Shut-off power mains Disconnect telephone Unplug electrical items to protect from lighting Stop newspaper delivery Turn off ice maker Turn off water heater Unplug major appliances Water plants
  14. In Brasil, put to work for moving people at an airport . Interesting concept, the sail is exposed to air flow in a duct under the train, its 'mast' riding on a slot. Enjoy ----> http://www.aeromovel.com/technology.htm
  15. Thanks, John. It is not about superconducting magnets. For the first case, any plain DC motor has field electromagnets, (unless uses permanent magnets) Like an engine starter motor.. ----> http://k7nv.com/notebook/ppinfo/13ef4770.jpg Been "absurdly inefficient" about a century, but that is the way they are. Electromagnets for the field. Modern motors are using permanent magnets more and more since better low cost magnets became available.
  16. The fear of snakes has to be -Because they are deadly, -They have camouflage, -They lurk, -They are quick -And the risk of the time needed to identify if deadly (if you can tell) exposes you more to death. The sum makes the high level fear. If none was poisonous they would be not feared more than a lizard.
  17. A DC motor has two windings, one for the rotor via brushes; and one for the stator to create the 'bias' magnetic field. Fed with separate supplies, the stator magnetic field consumes 1 Ampere at 10 Volts; and the rotor consumes 2 Amperes at 10 Volts. That is 10 + 20 = 30 Watt, and the water pump it drives rises a column of water 25 metres high. That same motor gets a transplant of its stator electromagnets, replaced with permanent magnets that produce the same exact magnetic field. Now the motor driven water pump pushes water to the same exact height of 25 metres high as before in the same time, consuming 20 Watts by the rotor. What is going on? -The same work in both cases with now less power demand- How stupid is to say the magnets are contributing with 10 Watts worth of power ? ... Or... saving 10 Watts worth of power ? What is the mathematical analysis ?
  18. Hi. The leftmost in the picture is 30 months old, 15 inches tall. The rightmost is exactly the same age sibling, all his life kept in a sealed test tube, 2 inches tall. Both seem very healthy. The central one was captured being ~ 1 year old, living also well in a tight closed jar. -----> http://i588.photobucket.com/albums/ss323/Innernet/Junipers_zps94787729.jpg What impairs the growth but sustains life in the captive ones ? Lack of nitrogen getting in ?
  19. I truly love and enjoy all kinds and colors of dead snakes. Two hours ago, the 18 month-new neighbor stepped on the tail of a copperhead while going to the back porch. Her mom is still in panic. -Did not bite-. I volunteered to mow her grass to calm her when she returns home by night.
  20. Hi. Can PET be 'converted' into thermoplastic ethylene vinyl acetate EVA, polyamide, polyethylene, or polyolefin by some not too complex process ?
  21. Asking the opposite would be more 'normal' ; that thread already exists... The brain size has an upper limit, so, In your opinion which animal is the most stupid of all ? Downward in scale, the tiniest brain should fall into insects and perhaps microorganisms, and opinions on the most stupid creatures can fall in a grey area, but, Do you have of a notable choice ?
  22. Radar imaging of the Sahara desert shows rivers carved rocky soil underneath the sand. Where did all that huge amount of sand migrated from carried by winds, or was created and ended deposited there ? Is the sand depth currently increasing or decreasing ?
  23. Hello. 1. Amps written on the Solar PV as 6 or 7 amps are 6 amps/hr? Or does it means something else? It is 7 Amperes. If delivers energy during 4 hours, will be 7x4=28 Ampereshour 2. How many hours will my solar panels take to charge my two batteries? (I understand that there is a solar charge controller in between to control) If you can give the calculation, I would really appreciate. From a halfway charged state, say 2 batteries at a point capable of only 100 Amperes each; At 7+7+6= 20 Amperes, should take 200/20=10 hours. At full sun. Not a precise answer but should help you. 3. What is required to charge battery - voltage or Amps or both? Is it correct to say that to charge my 12V 200 Amp battery, I would need to charge it with 12V 20amps for 10 hours? A single 12V battery should receive more volts applied to it than its current charge state, limited to 14 V for charging (28V for two) 3. Is 24V 7amp = 12V 14 amp? Yes, you can say that There is a few possible configurations for the items you have. The one I would chose would be as picture attached next. will supply 24V at 200 Amperes capability. Unless there is an error in the 'inverter' specifications being really 24VDC in and 120VAC out; I see no need for it applying the schematic above. If it really is 24VDC in and 120VAC out, just connect it to the bottom arrows in proper polarity. ======================================================================= Second way, attached below.. This will supply 12V at 400 Amperes capability, and uses your converter.
  24. Is it known if all bodies there orbit in the same direction as the planets ? Is too much of a coincidence everything in the solar system orbits in the same direction, or is there a reason ? If an old planet existed in the asteroid belt and collided with a counterdirection 'visiting/errant' body; would that create an asteroid belt ?
  25. Which way does the current members ranking works ? Any link to forum rules about it, please ? If not functioning, why not deleting such username titles ? If functional; what is the scale ? Thanks.
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