mrfox

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About mrfox

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  1. Mathamatically its a momentum exchange tether in reverse. Similar to what is described here - https://www.google.com/url?q=http://scholar.google.com/scholar_url%3Furl%3Dhttps://arc.aiaa.org/doi/pdf/10.2514/1.44873%26hl%3Den%26sa%3DX%26scisig%3DAAGBfm2VpLOITVrFPGnL9pQmXMIEjv9YTQ%26nossl%3D1%26oi%3Dscholarr&sa=U&ved=0ahUKEwi2656I19rbAhVl6oMKHWy8BosQgAMICygA&usg=AOvVaw3KSueYLqXEqnt0gjQjnV6O The structural requirements to intercept inbound objects at interplantery speeds would be substantial. Hopefully by that point in our evolution we have figured out better power sources - analogous to how modern solar panels have taken the place of mercury boilers in early sci-fi.
  2. the question is less a physics problem, rather its a great lesson in how vaguely/poorly defined scenerios can cause angst and confusion - because everyone assumes their own 'obvious' assumptions to the question are... obvious.
  3. These would be belts used for power transmission/timing/sync applications - similar to the belts you find in a car engine. Fastest conveyer belt is apparently 'only' 15m/s (30 knots) at a german mine
  4. Quick google search shows max rated belt speeds today to be around 100m/s - around 200 knots - so it seems for high speed airplanes (most large airliners today have rated max tire speeds around 230 knots) both the belt and the wheels would fail around the same time. The belt would heat up just as much as the tires would due to the mechanical deformation of the material as it bends around the rollers.
  5. The effect would have been even better had they had some sort of speed indication for the turntable, plane and car wheels, and forward ground/airspeeds for the vehicles, but nevertheless a fun museum exhibit (photo lifted from newspaper article)
  6. mrfox

    Bad science in fiction Hall of Shame

    How about the movie Sunshine? Like interstellar - such an interesting premise, if they could've only come up with a slightly more plausible plot device, and a little more care and attention on the science and physics... Like interstellar - so much story potential presented in the first half - but all wasted at the second half by sterotypical hollywood tropes. What really grinds me about these two movies was that I was really excited about seeing them when they came out - what a shame.
  7. mrfox

    Bad science in fiction Hall of Shame

    For me, the key in a immersive scfi story is not total realism, but the suspension of disbelief. And the good ones does this by presenting a consistent narrative that, although not 100% realistic in "our" universe, makes logical sense given the rules of "that" universe. Hence, Gravity works for me. And so does Galaxy Quest. Because they don't pretend to be "hard" scfi. And Interstellar doesn't. Because it tries too hard to be "hard". The inconsistency grinds when you manage 8/10 for astrophysics, but 0/10 for engineering physics.
  8. mrfox

    Catapult start?

    https://en.wikipedia.org/wiki/Mass_driver https://en.wikipedia.org/wiki/Space_gun
  9. https://batterybro.com/blogs/18650-wholesale-battery-reviews/98659398-electric-jumbo-jets-how-many-batteries-do-you-need-to-get-airborne
  10. https://en.wikipedia.org/wiki/Contra-rotating_propellers Contra-rotating propellers on a Rolls-Royce–Griffon–powered P-51 Contra-rotating propellers of a Spitfire Mk XIX One of the quartet of contra-rotating propellers on a Tu-95 Russian strategic bomber XB-35 Flying Wing shown its quartet of pusher contra-rotating propellers. https://en.wikipedia.org/wiki/Coaxial_rotors Kamov Ka-32A-12 Russian Air Force Ka-52 Sikorsky S-69/XH-59A
  11. Think about it - every bolt of lighting in a storm generates a shockwave. Its call thunder. The answer seems obvious.
  12. I believed a far side landing was one of the myraid of proposed missions for the later cancelled apollo missions. The CM would serve as comms relay when passing overhead, but there certainly would've been a lot of alone time on that mission.
  13. a good sci-fi/horror game with an interesting premise on this very topic https://en.m.wikipedia.org/wiki/Soma_(video_game)
  14. http://m.scmp.com/news/china/economy/article/2060544/made-china-triumph-china-declares-it-can-make-ball-pen-head Even something as simple as the metallurgy of a pen tip requires years of effort and research when you are starting from scratch.