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swansont

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Everything posted by swansont

  1. In a very naive sense, sure. Learning the top 100 things that can kill you might add stress; instead of a generic knowledge that things could kill you, now you know specifics (plus, people are bad at assessing risk, especially when it's small). But this knowledge means you can take steps to reduce the risk of these things killing you, so ultimately this represents less stress overall. Where do vague talking points show up on the list?
  2. Showing up in the same equation (for a planck unit, no less) does not make one depend on the other.
  3. Planck's constant is related to c? How? It is true that c shows up in many places, but for this to be a problem it has to vary by location, as well as between frames. The problem is that if it isn't, physics doesn't just break in the one or two ways you want it to. It breaks in may ways. Ways that we have good evidence that it isn't broken. Markus gave three different views of the big picture. And you have provided...nothing.
  4. If that's what it says, it's wrong. (trivially so; if we assume "it's gravity" refers to the gravitational acceleration, we can see M/r does not have the units of acceleration. Doesn't have units of force, either, so the two likely suspects are eliminated) The gravitational acceleration of the earth is g = GM/r^2
  5. That's only because the invariance of the speed of light has been established to the point where we rely on it for our standards. The standard for distance used to be a physical artifact. The standard for time is the ground-state hyperfine transition in Cesium, which is not directly dependent on c.
  6. Can you export the data? Any graphing program should be able to display two waves
  7. Signals that are added out of phase tend to cancel. I would imagine a circuit designed to do this would have the ability to adjust this and maximize the signal (or you could do this by changing the locations of the antennas; a signal at e.g. 300 MHz has a wavelength of a meter) but it means you can’t just combine them as you want.
  8. These are not even remotely the same thing, so no. Perhaps you could describe this situation in a less insulting manner.
  9. drumbo has been suspended for soapboxing and violating our civility rules
  10. 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.
  11. ! Moderator Note “it is well known’ is poor science. This will not fly. Do better.
  12. By all means, let’s just let anyone be a physician/engineer/scientist/ etc. without regard for their intelligence. What could go wrong?
  13. Distance is relative. It depends on the frame in which it is measured. You have not connected these. How does NLR relate to convexity?
  14. ! Moderator Note Citation? This is a science discussion site. Please give responses based in science
  15. 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?
  16. 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
  17. 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
  18. 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.
  19. Actual, mainstream scientific principles? Not the pulled-from-wherever mumbo-jumbo in your first post?
  20. 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)
  21. 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."
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