Skip to content

exchemist

Senior Members
  • Joined

  • Last visited

Everything posted by exchemist

  1. You can do plenty of experiments that don't involve anything electrical at all. So it doesn't seem to me that trying to relate the information obtained from an experiment to voltages is a particularly helpful line of enquiry. Arfa?
  2. Why are you muddling up sound (i.e. pressure) waves in an easily compressible medium, like air, with surface waves on the surface of a liquid? The restoring forces in these two cases are due to quite different things.
  3. If your floor is reasonably clean, then I think the bigger issue will be the fact that the food has been exposed to the microbes in the air, because of the hole, for perhaps quite a long period. You don't say what this meal consists of (whether dry or wet, cooked or uncooked, etc). If it was a hot, cooked meal such as a stew, that was supposed to have been sealed from the air in a sterile state after cooking, then you might want to be a bit careful if it has been kept in something with a hole in it for several days. But I really doubt that a few seconds contact with a clean kitchen floor will do much harm.
  4. I'm not what sources you are relying on but in the UK here seems to be a fair amount of evidence that the vaccines work pretty well at reducing the severity of infection with the Omicron variant. There is a paper here on it: https://www.gov.uk/guidance/monitoring-reports-of-the-effectiveness-of-covid-19-vaccination And here: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1046479/S1479_Imperial_Severity.pdf
  5. No it doesn't. Human beings can be seen to be close relatives of the other apes. The relationship to other animals is plainly more distant.
  6. A few observations: We do not know what happened before the Big Bang. It is conjecture. Extrapolation points to a singularity, which would in some models have represented the start of time, in which case there could not have been anything "before". But we don't know if such extrapolation is valid. So what you have written is not "pure science". Absolute zero relates to temperature, the temperature at which no more heat can be extracted from matter. That has nothing to do with the dimensions of the cosmos. So far as I am ware, the term "virtual number" relates to telephone numbers. Zero is a point on the the real number line. But this is the case irrespective of any cosmological model.
  7. Yes under those conditions surface tension provided a (very small) force that seeks to minimise the surface. OK, I should have said "behaves elastically" rather than "is elastic". Is that better?
  8. Sure, but that is not responsible for the restoring force in surface waves on a liquid, which is the the scenario under discussion. That restoring force is gravity, which is not intrinsic to the material.
  9. There was a young man named Green, Who invented a w*nking machine. On the ninety-ninth stroke, The bloody thing broke, And whipped his balls into cream.
  10. A liquid, however, has no shape. It takes on the shape of its container. @Ken Fabian's comments seem to be spot-on. An elastic substance resists deformation, by means of a restoring force generated by the material itself. It is rather perverse to maintain a liquid is elastic, when the only force restoring the surface to flatness is external to the material, viz. gravity.
  11. I agree, but another crucial point about laws is that they represents a common, agreed standard by which conduct can be judged by the community. Laws remove the arbitrary element in deciding whether conduct is acceptable and thereby enable consistency and fairness - which in the end stops us all fighting one another in private disputes.
  12. Professor Bargh sounds like a Private Eye joke. But I mustn't be bitchy...... Seriously I'm not sure how any of this can be applied. Personally, when I find myself in conversation with some who recites a lot of words like respect, respectful and patient, I find I soon want to get away, before my toes start curling.
  13. I may be being a bit thick, but I don't understand these diagrams. Space-filling models are fairly useless at showing bonding and they don't seem to relate to the stick models beneath. Leaving them aside, what is meant by the red and yellow dots in the centres of the hexagons? And how can one tell which atoms are nitrogen?
  14. Cult? Slavery? I have to say that - exercising my right of free speech - I am put in mind of this:
  15. I agree that a "conflict model" between science and religion seems fairly ridiculous, given the number of scientifically literate people with religious faith, and given a knowledge of what many religions actually teach (as opposed what people like Dawkins might have you believe). There is however a conflict between science and a particularly noisy strand of American Bible Belt Protestantism*, which can lead to a misleading impression, especially in the USA. There is a detailed discussion of all this here: https://plato.stanford.edu/entries/religion-science/#ModeInteBetwScieReli. which gives a more balanced view. * It seems to me there is a certain irony here, in that there is a case for arguing the Reformation originally gave quite an impetus to the development of modern science, only for some of the products of that Reformation to repudiate science today!
  16. The normal meaning of elastic is to a material that returns to its shape when a distorting force is removed. So that would not apply to a liquid, surely? What spatial derivative do you mean?
  17. Strange. What's all this about the supposed absence of free speech? Have you had some personal crank theory rejected, or something?
  18. I do not think what you say it true. Most scientists, it seems to me, don't give a moment's thought to the question and simply accept the values of the fundamental constants are what they are. So in effect your "so what" option is what they subscribe to, by default. I think you are making a fuss about nothing, to be honest.
  19. This seems very naive. The attractiveness of a person - which is about more than looks, of course - is a far more complex thing than can be shown in a photograph. And exactly the same applies to the women that men choose, of course. But perhaps you are too young to have personal experience in such matters.
  20. I think that statement makes no sense. I also think that, for a teacher, you are not very good at spelling. 😁
  21. The metal flanges and overall size suggest a commercial setup of some kind. I'm wondering if, as an alternative to handling materials at low temperatures, e.g. liquified gases, it is possible this was designed for some sort of biological growth process requiring close control of temperature. But I am speculating wildly and have no more to offer, I'm afraid.
  22. There is no real evidence that throwing more money at fusion would speed anything up. The science goes at the rate it goes. And what we spend on climate research is probably fairly small, by comparison with the cost of ITER. Most of the climate change expenditure seems to be on what to do about it, which you have to keep spending.
  23. There seem to be several different items here. Where did you get them and were they part of a set? First reaction is that they seem to be silvered. Is that right? And could they be double-walled? They remind me of double-walled vacuum flasks used to handle things like liquid nitrogen. Those are silvered, to reduce heat transmission by thermal radiation. I see the spherical one has ground glass joints at either end. Also these pictures are very poorly lit. Can you not illuminate them with daylight instead of a computer monitor?
  24. Perhaps not (though it probably does). However there are other standpoints besides the biological one. It interests me me from the standpoint of physical science.
  25. In fact, though, these projects were decided upon years ago. ITER - which JET will hand on to - was effectively started back in 1987. Though it is true that more partner countries (e.g. India, Australia) have joined the project in the last decade or so. But fusion remains a "jam tomorrow" energy source that will only contribute, if it ever does, in the 2nd half of the century. Given that state of affairs, it is actually quite remarkable that there has been the - global - political will to fund something so expensive, so long term and so uncertain.

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.

Account

Navigation

Search

Search

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.