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Everything posted by swansont

  1. drumbo has been suspended for soapboxing and violating our civility rules
  2. This cites facial characteristics. Your claim was much broader. Further, the focus was on whether hormones affected the preferences, not on what the preferences are.
  3. ! Moderator Note “it is well known’ is poor science. This will not fly. Do better.
  4. By all means, let’s just let anyone be a physician/engineer/scientist/ etc. without regard for their intelligence. What could go wrong?
  5. Distance is relative. It depends on the frame in which it is measured. You have not connected these. How does NLR relate to convexity?
  6. ! Moderator Note Citation? This is a science discussion site. Please give responses based in science
  7. Of what utility is it that we “must” introduce this? In what calculation would it be used? You insist that NLR > 0, and then ask if it is. If you don’t know, don’t assert. What useful information do you expect?
  8. Humans are powered by food, and as a result are incredibly inefficient sources of power. Much energy is wasted in obtaining food, especially if you are not following a vegetarian menu
  9. Power loss is given by P=IV Same current, lower voltage would have a smaller loss. No, you should not. You deliver less power at the lower voltage when the current is the same. 1000V 5A is 5 kW. 100V 5A is 500 W. But I agree with what others have said - defer to electricians following code for home wiring projects
  10. Yes, the voltage drop is another consideration. For a 100m run, you may want a thicker wire, but one should note that the calculation assumes you are running maximum rated current through the wire. From an electrical contractor/regulations/house wiring code point-of-view this makes sense and should be followed, but it's the worst-case scenario - if you're doing a hobby project and you absolutely know that the current you'll be using is 1/10 of the max, then the voltage drop is also 1/10 of the value the formula gives you.
  11. Actual, mainstream scientific principles? Not the pulled-from-wherever mumbo-jumbo in your first post?
  12. The heat dissipation is based on P = I^2R, so lowering the voltage and increasing the current means more power dissipated in the wire. P = IV would include the voltage drop across the load, which should be much larger than the drop along the wire itself. IOW, if you have a ~1.1 kW device, at 1100 V it draws 1 A. At 200 V it requires 5.5 A. The power dissipated in the wire goes up by about a factor of 30 (though for a length of wire with a resistance of 0.1 ohm, this is going from 0.1 W to ~3 W. That's the issue. It's negligible in terms of the overall load, but can be significant for a thin bit of wire)
  13. If it's the same power, you can use P=IV It's whether the wiring is in a conduit or in open air. Ratings for in-conduit (or grouped) vs unenclosed have to do with heat dissipation and the temperature the wire might achieve https://en.wikipedia.org/wiki/Ampacity "The allowed current in a conductor generally needs to be decreased (derated) when conductors are in a grouping or cable, enclosed in conduit, or an enclosure restricting heat dissipation. e.g. The United States National Electrical Code, Table 310.15(B)(16), specifies that up to three 8 AWG copper wires having a common insulating material (THWN) in a raceway, cable, or direct burial has an ampacity of 50 A when the ambient air is 30 °C, the conductor surface temperature allowed to be 75 °C. A single insulated conductor in free air has 70 A rating."
  14. Right, arrival time is 11:00, so the clock reads 11:00 You have not established any reason why the clock would not tick during the trip. It's just something you've asserted with no justification.
  15. Do you have data on the impact of wood vs fossil fuels? Both put CO2 into the atmosphere. edit: "burning wood emits more CO2 than fossil fuels per megawatt-hour (MWh) of electricity generated or per unit of heat generated." https://www.wri.org/blog/2017/12/insider-why-burning-trees-energy-harms-climate Plus, you've cut down a tree, so you have lost a sink of CO2. It will take years before a new tree will sequester the amount of CO2 you released. That's selective cutting which is more expensive and takes longer. You also tend to take the best trees out of the ecosystem. If you burn all the trees, does it matter of you burned N trees per square kilometer or N/2 trees?
  16. What's the point? Relativity is how nature behaves. Why is it 10:00? The missiles did not send the signal at 10:00. At 10:00, the clocks were co-located. There is no other time on the trip the clock would read 10:00. At B, the clock said 11:00 Why would it stop ticking? Do you have a model which predicts this, or is this just more flawed logic?
  17. No, they generally don’t. Do you have a specific example in mind? Evidence? Evidence? and again: evidence? It has? Long on BS, short on facts. ! Moderator Note You need to do a lot better to be in compliance with our rules
  18. It’s as Janus says. There are no effects other that signal delay, which is rather mundane, since it’s part of everyday life.
  19. I agree. Much about the accomplishment is impressive, but they choose to hype something that's rather mundane.
  20. ! Moderator Note Discussion of whether relativity is just light propagation delay has been split https://www.scienceforums.net/topic/123006-time-dilation-is-propagation-delay-split-from-what-is-time-again/
  21. We are assuming there is no time dilation in this scenario. There is no relativistic anything. The premise is that light travels at a finite speed, but not that it is invariant.
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