

John Cuthber
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Everything posted by John Cuthber
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What do BS of Physics graduates actually do?
John Cuthber replied to Elite Engineer's topic in Physics
I think a lot go into finance. -
Polystyrene absorbs a lot of UV- in particular it absorbs the UV that polystyrene absorbs (yes, I know that's tautology). How well do you expect it to reflect the UV that's absorbed by ABS? (The S in ABS stands for styrene). The cotton sheet is a better idea, but wash it without laundry detergent a couple of times to remove the fluorescent brighteners. Incidentally, most white paint is largely based on titanium dioxide which also absorbs UV heavily. Aluminium foil is probably as good a suggestion as anything,, but if you focus the sun too well you will melt the plastic.
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Why have you put the capacitors in there? (It still won't work without them, but they will stop any current flowing once they are charged, and that will only take something like 2.7 µ Coulombs.)
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Doggy, You might start by reading this https://en.wikipedia.org/?title=Nernst_equation
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can a strictly steady repeatable diet delay (or even prevent) aging?
John Cuthber replied to minaras's topic in Speculations
Not that anyone will care about my opinion greatly, but I have to second that. I'm happy to eat golden syrup and brown sugar sandwiches if there's nothing else to put on the bread and I always have at least 3 sugars in a cup of coffee, but even i found many US breakfast cereals to be over sweetened when I visited. On the other hand, the thing that really struck me in terms of the local diet was the size of the portions. BTW, I realise this is a bit OT, but as far as I can tell, the OP's question has been answered. -
can a strictly steady repeatable diet delay (or even prevent) aging?
John Cuthber replied to minaras's topic in Speculations
There are, it seems, (at least) two schools of thought about Calorie counting in food. One takes account of the fact that, for example, digesting nuts takes some energy while digesting sugar takes much less. The other relies on calculating essentially the heat produced by burning them. If you take the former approach then it's almost tautologically true that 200 Calories is 200 Calories. I think that most of us would accept that (for most people, most of the time ) 200 Calories worth of nuts would be a better option since it would also add some fibre, minerals and vitamins to the diet. If, on the other hand, you are allergic to nuts... -
can a strictly steady repeatable diet delay (or even prevent) aging?
John Cuthber replied to minaras's topic in Speculations
You seem to have cited a wiki article about a film. Do you have a more robust evidence base? -
can a strictly steady repeatable diet delay (or even prevent) aging?
John Cuthber replied to minaras's topic in Speculations
That is plainly silly. If the weather is hot you need to drink more water to replace that lost through sweating. So a constant diet would either be short of water in hot weather or it would have too much water in cold weather. Not in terms of weight loss; they are as good or bas as eachother. -
It's almost as if Hagar never had any intention of coming back and responding to the points raised...
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Base 256 character set, and "Base Byte" numbering system.
John Cuthber replied to tar's topic in Mathematics
Indeed. What about them? -
Base 256 character set, and "Base Byte" numbering system.
John Cuthber replied to tar's topic in Mathematics
I didn't include this by accident. http://www.frenchtutorial.com/en/learn-french/pronunciation/alphabet -
Base 256 character set, and "Base Byte" numbering system.
John Cuthber replied to tar's topic in Mathematics
"Perhaps where I left this thought, before, was in coming up with a particular way to pronounce 0,1,2,3,4,5,7,8,9,A,B,C,D,E,F " un deux trois quatre cinq six sept huit neuf dix http://www.frenchtutorial.com/en/learn-french/pronunciation/alphabet You are stuffed with F which is pretty similar in English and French. You might have to try German or something. -
A misunderstanding about multiplication
John Cuthber replied to Deepak Kapur's topic in Classical Physics
Yes it does. It's the area of the "thread" of fuel that you would have to leave on the ground if, rather than having a tank, the vehicle picked up its fuel from the floor as it went along. It's a physical meaning, but not very useful. -
Base 256 character set, and "Base Byte" numbering system.
John Cuthber replied to tar's topic in Mathematics
This lot would have got you most of the way there more than a third of a century ago. https://en.wikipedia.org/wiki/PETSCII -
Thanks, my guess would have been Krakatoa but the principle is the same. Every now and then a big volcano chucks a lot of dust into the earth's atmosphere and it gets chilly for a year or two until the rain washes the dust out. Then the weather settles back down. None of that makes any difference to the fact that anthropogenic CO2 is warming the air. Can anyone see why Harold thought it was relevant?
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"Over the entire history of the human race even though technology has expanded drastically there humanity has fallen by the wayside." In what way?
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A question about proportionality and equality
John Cuthber replied to Deepak Kapur's topic in Classical Physics
I doubt that. It's true for self-consistent units but if I choose to measure force in dynes; momentum in stone furlongs per fortnight and time in jiffies it's going to go to hell in a handbasket. None of that detracts from the fact that the best thing to do with BR-549's "contribution" is to ignore it -
you don't seem to have understood. You won't be banned for saying that. You will be asked to demonstrate that there is at least some evidence for it. If , rather than providing evidence, you keep onposting the same unsupported assertion, you will probably get banned. As far as I can tell, (and it's difficult because of the way you write things) you mean that something like this happens CO2 for some reason falls apart to C and O2 The C reacts with water to produce HCHO That's unrealistic, but at least it is testable If there were carbon atoms floating round in the atmosphere we would detect their absorption spectrum when we looked at sunlight We don't. So that's it. The hypothesis leads to a testable conclusion; the conclusion is found to be false, so the hypothesis is false. For what it is worth the hypothesis that formaldehyde is a step in the photosynthesis of sugars was first put forward by Baeyer in 1864. It was wrong then too.
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Perhaps you should stop embarrassing yourself; Farrady cages can have holes in as long as they are small compared to the wavelength of the radiation. Did you think things through, and enclose the Geiger counter in a metal mesh cage to stop RF interference? If not, do you realise that the experiment was meaningless?