Everything posted by John Cuthber
-
What's the major difference between cheap and expensive wine?
Oops! Someone changed the rules while I wasn't looking.
-
What's the major difference between cheap and expensive wine?
An important factor is that stronger wines are more expensive (for tax reasons) and also more harmful to health.
-
Today I Learned
In case anyone wondered, yest this does belong with the jokes. The Equipment The equipment used in these two sports is another major difference between them. For a start, the pin pong table, about 3.7 mm in diameter, is slightly larger than the table tennis court, which is only 3.4 mm. Source: https://pingpongacademy.org/ping-pong-vs-table-tennis/ I'm just not sure if it's deliberate.
-
Enough of crackpots, how would you have got on in an 1859 school exam ?
I must have been half asleep when I posted that or something. The longitude- almost exactly 30 degrees- is the one that matters . The time difference should be almost exactly 2 hours. Today I think the answer is 3 hours, but that 's largely political.
-
Is homogenous viscosity a good indicator for general homogeneity in mixing?
That seems sensible to me. Even if the materials have the same viscosity to start with, a mixture may have a different viscosity (anyone who has seen an engine where water has got into the oil will know that; the product is much more viscous than the components even though no chemical reaction takes place). So, if the viscosity is homogeneous, the mixture must also be. But there's a catch 22 here. If your model doesn't work, then using a modeled property- like viscosity- won't be a good test. If you could model the density (which is usually "better behaved"than viscosity) it would be better.
-
Enough of crackpots, how would you have got on in an 1859 school exam ?
7/8 and, had I been a Victorian schoolkid, I might have swotted up on lowest common multiples. That might not have been a time zone. It's pretty close to exactly 4 hours. " St Petersburg, Russia Lat Long Coordinates Info The latitude of St Petersburg, Russia is 59.937500, "
-
Sargassum problem
Thanks for the warning I will seek to avoid eating insulating materials.
-
Sargassum problem
Can we haul it out, dry it and burn it for fuel?
-
Bouyancy of a contained helium gas ?
To a very good approximation, the effect of temperature on the density of air and helium is the same (in percentage terms). The balloon floats because its average density (including the walls of the balloon)is less than that of the air. As the balloon rises the air gets less dense. There comes a point where the density of the balloon and the surrounding air are the same and, at that level, it stops rising. It's made slightly more complicated by the fact that the balloon changes volume (and thus density) as it rises.| With mylar balloons, once the envelope is "full", the volume stays pretty much constant (until they burst). High altitude balloons are launched looking rather empty, to allow for expansion as they rise. https://www.forbes.com/sites/elizabethhowell1/2019/07/05/google-affiliated-company-sends-high-altitude-balloon-aloft-for-223-days/?sh=484528407edf
-
is it good or bad to clean something made of kind of wood?
Note that not all epoxy resins are food-safe. Essentially the OP's question is like going into a large DIY store and asking "which is the best paint?". You might get an answer - but it might not be the information you were seeking.
-
Is it possible to artificially synthesize proteins?
Not really. Ivory is a combination of mineral material (largely hydrated calcium phosphate, I think) and proteins (largely collagen). Collagen isn't hard to get; nor is the calcium phosphate. But combining them is impractical/ impossible. The good news is that the only thing that ever needs ivory is an elephant, and it can make its own.
-
Is it possible to artificially synthesize proteins?
Yes, it is. What's to discuss? https://en.wikipedia.org/wiki/Cell-free_protein_synthesis
-
is it good or bad to clean something made of kind of wood?
The wood preservatives industry would not see it that way.
-
On the lab leak theory
Yes. It's called "air travel".
-
Vigilante post graveyard
I think we might as well treat the OP's "message" as spam.
-
How do Atomic Nuclei 'know' what the Temperature is?
When you get cold enough for spin energy to be significant, most things (including nitrogen) have already frozen solid. So you don't get the same effects that you see with hydrogen and deuterium (and, I guess, tritium if you have any).
-
Restaurant food (split from Heat Regulation - Obesity)
To be fair, that's a population size bias.
-
Restaurant food (split from Heat Regulation - Obesity)
And you picked "beige" from all of them.
-
On the lab leak theory
Did they look at the right time, i.e. before they knew there was an outbreak? Did they look in the right place, i.e. at every (susceptible) animal there? One odd case in some animal that passed the bug to a store-holder before becoming someone's cooked dinner would be all it took. Obviously, you can't rule out a lab mistake as the "source" but you have to ask how the virus got into the lab. It must have been in the environment somewhere. How easy is it to rule out the idea that, rather than coming from the lab, it came from the tyre of the car that carried the sample to the lab? Lab escapes happen. https://en.wikipedia.org/wiki/2007_United_Kingdom_foot-and-mouth_outbreak And they knew they were dealing with a dangerous (Cat 3, I think) organism. The only way in which you can "blame China" is if you can be sure that they deliberately made a lethal human pathogen in what is- as you say- pretty much a school laboratory.
-
Does microwave kill bacteria?
It depends on how hot you get them and for how long. it does not depend on whether you heat them in a microwave or not.
-
On the lab leak theory
Which would be the appropriate control measures for a bat virus, and vastly more than those in a wet market.
-
Matt
Water is black to UV with a wavelength below about 200 nM. But so is air, so it doesn't usually matter.
-
How do Atomic Nuclei 'know' what the Temperature is?
"How do Atomic Nuclei 'know' what the Temperature is?" They don't. They get batted about by the laws of physics and we interpret the way in which they behave as meaning that they have a temperature.
-
Should Homeless Addicts Be Removed From Cities?
That's pretty close to the same thing. Here in the UK, at least in principle, "just compensation" is decided by a jury of your peers.
-
g/G = 1 AU. Discuss
And if I did point out why he's wrong and you ignore that simple fact, it shows that you are not here to do science. And here's where I point it out. More importantly; I'm not attacking his credentials as a physicist. I am pointing out that he has no credentials as a physicist. His video is no more "valid" than a high street butcher telling you that physics is wrong. The difference is that the butcher does a useful job. At 11 min 22 sec or so he says that he doesn't understand the measurements. At 12:57 he says G has varied in recent years. How is he defining "recent"? But the point is moot. The "measured" values change- it's called experimental error. That's not the same as saying the actual values change, is it?