Jump to content

swansont

Moderators
  • Joined

  • Last visited

Everything posted by swansont

  1. In addition to your lack of air flow analysis, you haven’t shown how quickly the virus, much more massive than air molecules, would get up to speed.
  2. The last straw? For some, perhaps. But I am reminded of the tweet from Dan Hodges regarding Sandy Hook “In retrospect,” wrote Hodges, “Sandy Hook marked the end of the U.S. gun-control debate. Once America decided killing children was bearable, it was over.” (from https://www.miamiherald.com/opinion/op-ed/article33250299.html) I think the same sentiment applies here. Previous incidents, almost too numerous to mention, should have been the last straw — and weren't. Too many have decided this is tolerable, or ignorable. IOW, I wouldn't hold my breath hoping that this one incident swings the pendulum very far. People who have tolerated this kind of violence over time aren't going to be swayed. They are more incensed by Colin Kaepernick taking a knee. Pointing out the racial injustice hurts them more than the injustice. What I think is more likely is that reform comes if we vote the people who have supported or tolerated this kind of behavior out of office, but they will be voted out for other reasons as well. If that happens, this will be part of it, but nowhere close to the whole of it. edit to add: one difference here is Trump stepping in, owing to the protests. His anti-Midas touch might amplify things.
  3. This isn't an analysis, it's a hand-wave. You're making an assertion that isn't backed up by any analysis, and yet, this is a science site. It's not unreasonable to expect that this be backed up by some science and/or engineering. It also assumes you have a room where you can put that amount of vent area in the ceiling. You want a certain result, but have done little to show if such a result is feasible. You haven 't even done something simple, like showing that a 10' x 10' room with air moving at 2 mph / 3' per second in the middle means the air must be moving up to 12 mph at the vent (since it has to be moving ~6x faster if there's no change in pressure) and that this is moving 18,000 cfm through a single room. What kind of system handles that? What kind of pressure do you need in the ducts to get that kind of airflow? IOW, you can't just say "lets move the air in the room at 2 mph" and ignore all of the ramifications and system requirements, like you have a magic wand to make these other problems go away.
  4. Can/will you answer my question? And make no mistake, if you are proposing this mechanism, you are replacing GR.
  5. Gravity isn’t the only effect of GR. How does an “index” give rise to e.g. frame dragging? Or other effects of GR?
  6. Doesn’t matter if it’s obvious to you. Theory says the electron is a point particle and experiment backs this up. Can you transform into a frame where angular momentum goes to zero, the way you can with linear momentum?
  7. Are you arguing philosophy or physics? Last I checked, gravity was in the realm if science. IOW, what evidence do you have that e.g.an electron doesn’t experience gravity? And if they don’t experience gravity, do they also not exert gravity?
  8. Two clocks in relative motion will have symmetric time dilation values, based only on their relative speed. One clock has a different mass than the other, so they do not have the same momentum. It has to be a separate effect.
  9. That's not enough. This is physics; we quantify things. Is the amount of dilation from the momentum equal to the amount you'd get from gravitation? (AFAICT the answer is trivially no, BTW)
  10. That’s for you to show.
  11. What paper? Is there a link?
  12. A radiometer such as the one that was depicted does not work by radiation pressure. It rotates in the opposite direction. I don’t see that there is a connection here with a light clock, which is an idealized device and shows time dilation’s relationship with length contraction (owing to the invariance of c), rather than any real processes.
  13. Yes, that’s what relative means, That specific comparison is not what is meant by absolute. For example, observer C will not get the same answer. When different observers get different results, the results are relative. So yes, you need to pick a new term.
  14. Delberty has been banned for repeated violations of civility rules and not arguing in good faith.
  15. Explain how time dilation makes me fall down.
  16. Add me to the list. Clock rates are relative to your position in the well.
  17. There's a reason for that. Only radial movement gets you to a different gravitational potential. Your use of "absolute" here is not in keeping with how relativity uses it. Pick different terminology.
  18. If you take Myclock - Yourclock, the difference has a different sign for the two observers. And neither one can say theirs is "the" correct one
  19. pi * diameter does not get you an area. Wrong units. A = pi * r^2 = pi * d^2/4
  20. Wind tunnels literally have fans like this, but irrelevant if you are getting the same airflow from multiple fans. The air speed will be the same if you are moving the same amount of air through the same area. But if the air is moving slowly, it will not get sucked out of the top quickly. Here's where analysis comes into it, where you can avoid making potentially contradictory statements like this. Continuity matters in situations like this. You can't be moving more air in than you are moving out. Moving the air slowly is not in keeping with your desire to move air away from people quickly. Wild-Ass-Guess i.e. a proposal with no basis in modeling or analysis I suppose I was thrown by your statement in the OP where you said "You want the air to circulate so fast that if someone sneezes the water droplets will remain inside the room only a few seconds before it is sucked out the ceiling vent. " I've been basing my responses on what you said. Is this the scenario, or not?
  21. Energy efficiency would seem to be orthogonal to the discussion. Airbrush seems to be implying that a large area of small fans somehow inherently gives rise to a different flow rate than a large fan "All I can say is if you have many vent fans sucking air out the ceiling, rather than one big fan that creates a wind tunnel, you distribute the motion and increase the area of the air moving up and out the ceiling." Changing the are will matter, but in the above quote it's not at all obvious that the example is changing the area (from the term "big fan" and that wind tunnels generally have a fan as big as the tunnel) It's the speed of the air that matters. The speed of the air being greater near a nozzle is only true near the nozzle, and it's not a given that there is any nozzle in this problem. Mainly what I want is Airbrush to present some science or engineering to back up a claim, rather than a WAG. This being a science discussion site and all. The scenario is proposing that air is only around for a few seconds, which sounds like you are getting 10 or so room changes per minute, instead of per hour. To do this, the air has to move faster, regardless of how you do it. My point is having the air move 60x faster is not an imperceptible change, as was claimed.
  22. Changing the question doesn’t make the answer correct.
  23. You said yourself a wind tunnel has a big fan. Where is the constriction? I ask again: how is one big fan vs lots of small fans different? (same area)
  24. How is one big fan vs lots of small fans different? If you can’t model the behavior, how can you predict what happens?
  25. How about some math/modeling to back up this claim

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.