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John Cuthber

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Everything posted by John Cuthber

  1. Given a product of two primes n, and n+2 the product is going to be very close to (n+1)^2 So you can take the nearest integer to the square root of the product, and the factors will be that +/- 1 Eg. imagine I give you the product 19043 the square root of that is 137.996... Very close to 138 And the integers 1 away from it are 137 and 139. And those are the factors of 19043.
  2. The good news is that we are able to dismiss his views on the WHO.
  3. So, we dismiss Trump out of hand - because he was so wrong about lots of things. And, on that basis- we know that his views are often wrong. So, for example, since he didn't like the WHO, we can reasonably deduce the the WHO is probably a good thing.
  4. I'm not sure, but I think that they rely on the fact that the aluminium corrodes faster in more acidic soils and thus sets free more electrons which pass through the meter and give a larger reading. Or they may work on a principle is similar to this. https://en.wikipedia.org/wiki/Antimony_electrode How would that help find out how the meter works?
  5. I'm not sure i have understood this. Does this only work with primes where the two factors differ by two- which is interesting but not much use (I think there's an easier way)? If not, please show us how it works with 33,033,660,080,507 (which isn't a product of very big primes, just fairly big.)
  6. You can. Most of the UK’s electricity is produced by burning fossil fuels, mainly natural gas (42% in 2016) from https://www.energy-uk.org.uk/our-work/generation/electricity-generation.html Fridges move moisture about, but they don't "produce" much. A lettuce doesn't steam as much as a roast.
  7. Is it a gas powered refrigerator? Most electric ones are practically airtight and don't give off moisture at all.
  8. I always wonder if that was meant to be ironic. It is, at root, a commentary on people... Nearer the topic; Someone once described the House of Lords as "A very civilised way to look after the elderly". I sometimes think that government research labs are a very civilised way to look after us nerds.
  9. I'm guessing at a typo. https://en.wikipedia.org/wiki/Overtone And the idea of "concordance" or "consonance" is cultural, not mathematical.
  10. The octaves are important- as Exchemist has explained. If two notes are in harmony then the octaves above them will also be in harmony. The division of the octave into 5, 8 or 12 (or more) is arbitrary and largely cultural. Having said that, there does seem to be something about the pentatonic scale that people all seem to "get".
  11. OK, imagine I get some sort of electrical generator- perhaps a Wilmshurst machine, and I put it on an insulating slab like a thick sheet of polythene or something. And I set it running (let's say it has a battery drive motor, and a remote control- so I can do that without anything being connected to Earth). such that it charges the two spheres - one positive and the other negative with respect to eachother. And then imagine that I bring an earthed wire near to one of the spheres. What do you think will happen? Not very, and not for long.
  12. No, they were protecting the dollar. That's what they always do. That's what makes this so funny.
  13. And that is well within the range of typical static electricity. https://en.wikipedia.org/wiki/Static_electricity#Static_discharge You don't know much about this, do you? It isn't the charge that makes a difference, it is the voltage (though the two are related).
  14. And then they go back to sea level and perform better- because the increased oxygen is good for them. As with many things, there is a balance, too much, or too little is a bad thing.
  15. LOL https://en.wikipedia.org/wiki/George_Floyd_protests It went so well the last time they did that.
  16. True but: It's next to the two earthed metal screws that hold the cover in place, and you can make sparks by putting your finger near them. |It's also relatively thin plastic and may well conduct at the high voltages involved. And, of course, it may be a metal switch or a metal cover.
  17. By one convention, and by the other convention, both roots are considered as equally valid. For example, if you are solving a quadratic, you need to take account of both roots. https://en.wikipedia.org/wiki/Quadratic_equation
  18. I don't think this is an imaginary numbers problem. If the square root of x is minus one, then x = 1 is a solution. Root (1) = -1
  19. Then you will have no difficulty proving it.
  20. What you are talking about is a map that shows the presence of a gene in roughly 90% of "some population" in parts of N America. Well, if the population of the USA is 14% African Americans, 10% Irish Americans and 5% Italian Americans (virtually none of whom would have the gene) then the population represented on that map is not the population of the USA, is it? So, what are you talking about? Do you even know? Your claim is the opposite of the map you have linked to. You are going to need to work very hard to convince us that you are worth listening to.
  21. That's unrealistic, given how many are from, for example, Ireland ot Italy. It's even more absurd once you consider African Americans who form about 14% of the population. Are you able to explain this, or is your assertion simply incorrect? By which argument, most people in France, Germany < England and so on would be black. But they are not. And so we know that the argument is wrong.
  22. What do you think the word "acidic" means?
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