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John Cuthber

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Everything posted by John Cuthber

  1. Nice bait and switch there. The thing about "falling" is that it implies that the direction is "down" so there is information about a trajectory.
  2. Slightly less useful; you couldn't even fertilise the rose-beds with it.
  3. That's interesting. You could say the same of platinum and silver. But their relative cash values change.
  4. Not that I'm aware of and, if you are writing about something obscure, and fail to explain what it is, then you are writing badly.
  5. The spherical harmonics are not, themselves, spherically symmetrical. But the sum of the trio of P orbitals (one on each axis) is symmetrical.
  6. It's more than that. The atom can not know what axes you chose for your coordinate system and must therefore have an shape that is independent of your choice. The only way it can do that is to be spherical.
  7. The simple answer is that, according to our experiments, atoms are round. The case for non hydrogen-like atoms is complex, but the simple answer is that the orbitals we get have to be linear combinations of the corresponding orbitals for hydrogen (in order to meet the same momentum + energy criteria). So they look like these https://commons.wikimedia.org/wiki/File:D_orbitals.svg But what is never explained in those diagrams is that the actual sum of the functions is (So I was told as a student) spherically symmetrical.
  8. No Most of what we see as science is a complex interlinked grid of theories deductions and observations. And the important thing is that they all interact successfully.
  9. If you are going to try to be petty: get it right. It's a strontium ion. " The photo shows a pinprick of a positively charged strontium atom " If it was neutral, it wouldn't be held in an ion trap. Yes they are. Those funny looking dumbbell shapes you see are poor representations of the probability density. The actual functions sum to a spherically symmetrical distribution (unless there's one outside influence on them) But the biggest problem is this If I look at the end of my finger, what I see are photons that were emitted by virtual stated p
  10. https://www.nationalgeographic.com/science/article/trapped-atom-photograph-long-exposure-competition-spd
  11. Then I suggest that you get someone else to read your stuff before posting it. That way you might avoid saying things like "I read it twice before reading it ."
  12. Did you read that through before you posted it?
  13. The MSDS lists a couple of strong alkalis as the active ingredients and those will corrode aluminium. (To be fair, so will bleach) The problem is condensation. Have you considered something like this? https://www.selfadhesive.co.uk/tapes/single-sided-tapes/foam-tapes.html
  14. Am I the only one who read the title of the thread and thought "that's going nowhere fast"? IQ is barely meaningful, race is barely meaningful and brain size is barely relevant.
  15. And significant luck. There's no guarantee that they would be fissionable in a bomb. We simply don't know. It's possible that you could have a teeny little nuclear reactor- which would be cute, but utterly impractical.
  16. If you have symptoms which you think may be due to poisoning you should seek medical treatment. If it turns out not to be poisoning, they still need treating.
  17. How many "restrooms" does the Whitehouse have?
  18. "Does Hybridization Always result in superior genes?" It is impossible to define "superior genes" in isolation from the environment.
  19. You seem strangely determined to overlook the heat gun which is odd because the importance of heating is the point of the OP's question. You can demonstrate the effect of pH on the colour of tannins by making lemon tea or, less drinkably, by adding ammonia to tea.
  20. Acids are well known for catalysing the charring of carbohydrates. https://www.sciencekids.co.nz/experiments/invisibleink.html And it's a pH effect more than anything else. As you say there's no need for a heat gun
  21. I presume it's this sort of thing. (The commentary is inaccurate, it' s the HCl that chars the wood rather than the ammonia.) It would probably work in an oven but I don't know if "350 degrees" wold be hot enough. Units are important. There's a risk that the HCl fumes would corrode the oven too. The HCl is very corrosive towards metals (and not very good for people either).
  22. What worries me is that people may be leaving the party because they see it as no longer supporting their hero: Trump. OK that makes republicans unelectable which is good, but it is still terrifying that people might think that way. They might not be leaving because they recognise that the Reps are crazy; they might be leaving because use they don't think the reps are crazy enough. What happened to Rep party membership when he was selected?
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