Everything posted by John Cuthber
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Evaporation and condensation as a source of energy
Why would it do that?
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The Novak Djokovic Debacle:
From time to time people ask why the US immigration forms ask you if you plan to over throw the government by force. People laugh at this- after all- any actual revolutionary would simply lie about it. The point of the question is that, if it tuns out that you were planning a coup, the government can throw you out of the country for providing misleading information on your visa application. That's it; no court needed- no appeal. The thing that most people fail to recognise is that it's a general rule. If you get caught lying they kick you out. It's one of the more sensible things the US govt does. Most countries will do it, if they have the slightest reason not to want you in their territory. And Djokovic did not fill in the paperwork correctly. What did he expect to happen? I heard he intends to participate via Zoom.
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Bursting a metal pipe using freeze spray...
You might want to try dry ice, or even ice and salt because they are cheap.
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17 apples
Imagine I arrange the apples in three piles of 1, 8 and 8 apples. The two piles of 8 apples have the same weight. Imagine that I swap the single apple for one from one of the other two piles. The mass of that pile of apples must still be the same as the other pile of 8. But that's only possible if the 1 apple has the same mass as any of the apples in that pile. And that's also true if I swap the singleton with an apple from the other pile. In fact, there's no significance to the two piles of 8, you can consider them as a single pile of 16. The mass of that pile must be unchanged by exchange of any pair of apples. That's only possible if they all have the same mass.
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Are Vegan's, a help or a hindrance to, our future?
Who says it's a "benefit"?
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Are Vegan's, a help or a hindrance to, our future?
"Are Vegan's, a help or a hindrance to, our future?" Vegans may well be less of a problem than people who misuse apostrophes.
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What are you listening to right now?
Yes thanks. Partly because I was allowed to go out into the street to listen + watch. I'd just spent 10 days isolating due to covid. Quarantine ended at 1 minute to midnight.
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Galactic Redshift is not a Doppler Effect
My OP? Happy new year!
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What are you listening to right now?
I'm listening to the tail end of the fireworks celebrating the new year.
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Galactic Redshift is not a Doppler Effect
Where do you imagine that the energy goes? Here's a tired old theory that you seem to b trying to rehash. https://en.wikipedia.org/wiki/Tired_light#Specific_falsified_models
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How does one know how much a author contributed to a paper?
How does one know how much a author contributed to a paper? In general, you don't.
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James Webb telescope to launch today
https://xkcd.com/2559/
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Why did textbooks get so big?
"Why did textbooks get so big?" We learned more stuff...?
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Do angels have wings ? Were they created with wings ? Or an illusion people saw ?
No point asking then. Would a passing mod care to close the thread?
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How unsafe are the gullible ?
Yes they do.
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By which physical properties do isotopes actually differ
You seem to have it the wrong way round. The definition of isotopes is that they have different numbers of neutrons. Cooling oxygen until it liquefies does not change the number of neutrons. So it does not make any new isotopes. What changes is the temperature, rather than anything else. Isotopes have slightly different boiling points, but it is not the change in boiling point that makes them different isotopes.
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"Spontaneous" freezing of bottle of Topo Chico
The presence of an impurity such as CO2 will lower the freezing point of water. But my guess is that this is essentially a supercooling phenomenon.
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Pulverized leaves as fertilizer helper...
That's not about waste disposal, is it? So... No; hydroponics is not about waste disposal, but nor is the thread. Trying to get back to the topic isn't normally called "misdirection". It remains the case that improvements in fertiliser technology have been made since the Neolithic era.
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Pulverized leaves as fertilizer helper...
You seem to have missed the point. regardless of whether we are talking about "cave-men" using green manure or animal manure, the users of hydroponics think they have made an improvement over the Neolithic technology. It may have been key to Neolithic society. It is still important. However, it has, in at least some circumstances, been "substantially improved upon". (Unless, of course, you think the hydroponic farmers are actually using tech that is sells good than the traditional approach). You are technically right in saying it doesn't answer the question but consider this. "Is the Whitehouse made from cheese because of pressure from the dairy lobby?" Arguably, the answer to that is "no". But pointing out that the Whitehouse is not actually made of cheese is not a bad thing.
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Pulverized leaves as fertilizer helper...
Because they think they have made a significant step forward since the use of manure.
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Pulverized leaves as fertilizer helper...
The hydroponic farmers might argue about that.
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Roclket air polution
Not very relevant if you are using N2O4 as the oxidant. 😉
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Units?
Yes, I know but £ S and d are different units for the same thing. I can add a kilo of potatoes to a pound of minced beef adn an ounce of flour. But I don't get 3 anythings of stew.
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Units?
Yes, and he wasn't 9 anything.
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Units?
Did anyone suggest that they might be? It's "one whole anything" or "one of anything" but it's not "one whole of anything". One whole what? I guess it's "one whole instance of anything".