John Cuthber
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Everything posted by John Cuthber
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If I were concerned about any of those other sources of radiation (I'm not), I could reduce my net exposure by hiding behind a big lump of bismuth. It is damn near impossible to actually show that Bi is radioactive because it's roughly a billion times less radioactive that uranium.
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How happy are you about working with rather dangerous chemicals?
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Satellite Clock adjustment to earth time, how is it done?
John Cuthber replied to Alan McDougall's topic in Relativity
When all is said and done, the master atomic clock that runs the satellite will continue to oscillate at 9.192...GHz (give or take a defined and calculable offset due to the field) in its frame of reference. That's a little bit "wrong" from our point of view. As I said in the 7th post here "For a finish, I'm so glad I included the word primary in my earlier post." -
LOL I wonder if she has a mobile phone. There's no doubt that these bulbs emit RF noise and, if her complaint were that they might mess up AM radio reception then she would have a point. But the claim that the RF noise directly affects people is, to be polite about it, "unsupported by evidence". Remember, data is not the plural of anecdote.
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It doesn't matter if one of your predictions comes true. What matters is that many of them fail. Cavendish's experiment, the variation of the earth's gravity with latitude and the impossibility of orbits show that you are wrong. If you have an idea and it doesn't tally with reality, that isn't because reality is wrong.
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Pure capsaicin measures about 16,000,000 Scoville units So the hottest of your peppers contains (the equivalent of) about part in 16 of capsaicin. The red Savinia is a bit more than half that so it's about 1 in 32. So you can work through each one working out how much capsaicin is in it. Then you can multiply each of those concentration by the amount you added to the mix, so you add up 0.02 times 1/16 and 0.02 times 1/32 and so on to get the equivalent concentration of capsaicin in the mixture. From that, and the value for the pure material, you can work out the effective Scoville value for the mixture. But who cares? It's going to be pretty much inedible.
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I read your reply. But it doesn't answer the point. Cavendish (and later workers) demonstrated the inverse square law. If something varies as the square of the distance then you can't avoid having what you absurdly dismiss as "some spooky quasi-magnetic attraction between the two masses". And you have yet to answer the point about measurements of gravity that should easily pick up the effect of the Earth's tangential velocity- but don't. I say it's simply because the effect isn't there: gravity isn't produced by movement. How do you explain it?
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You can keep on emphasising it until you get bored of typing. It's still only 1200 times faster than the tangential speed of the Earth. I can measure the force of gravity to much better precision than that and it isn't affected by the Earth's spin in the way you say it should be. I was not kidding when I asked if you understood just how good a decent balance is. If you don't know then look it up. (And you have yet to explain the Cavendish experiment)
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The " Regulations which stifle business growth is obviously bad." argument would have gone down well with those who opposed the abolition of slavery. The trouble is that some regulations are a very good idea from society's point of view. As you say, it will be interesting to see if the regulations that R and R favour will be good for society or good for the rich. I suspect we know the answer to that.
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I'd go for a cold trap. Don't put anything in the gas washing bottle, but put it in a tub of ice and salt. (actually, I'd go for a better fume cupboard and, if I really couldn't do that I'd vent the ether vapour outside directly.)
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Satellite Clock adjustment to earth time, how is it done?
John Cuthber replied to Alan McDougall's topic in Relativity
OK. There's no disagreement here about the fact that the atoms absorb photons (and emit them in order to avoid problems with the conservation of energy). This document is a bit old, but I'm sure we can agree that NIST know about clocks. http://tf.nist.gov/general/pdf/1916.pdf On page 305 there's a nice simple schematic (another reason for choosing an old paper) of a clock and there's a box labelled " frequency multiplier and modulator control chain" which is shown as having an output to the electrodes in the gas cell. When the clock is running properly that µwave frequency is the resonance frequency of the atoms in the gas cell. I can count that. If I wait for it to tick 9,192,631,770 times, that's a second of local time. Whether I count that directly or use a phase locked loop to run a quartz clock at some known fraction of that rate and count the ticks of the quartz clock is not the point. The atoms ring at exactly the frequency they choose and if I want the clock to look like it ticks at 1Hz from down here I have to change the division ratio, not the frequency of the microwave oscillator. -
I thought that they tried that and the result was lots of sub-prime lending followed by a massive crash in the world economy. So it would seem that, while Romney + Ryan might save us from a world where your chances of getting illness treated depend on whether or not you have a credit card, it won't save us from a messed up economy.
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Do you know how good a modern analytical balance is? You can usually use a good one to measure changes in atmospheric pressure (indirectly). 1 part in 1200 would be trivial to measure.
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Things are moving faster at the equator than at the poles, but the apparent effect of gravity is bigger at the poles than at the equator. Once you allow for the bulge and the centripetal forces, the apparent weight is the same. Also Cavendish's experiment wouldn't make sense.
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Organic Synthesis of Molecules
John Cuthber replied to Aziz Sergeyevich's topic in Organic Chemistry
Sure about that? The C6 ring is roughly flat. Th C1 addendum can be above or below the ring. So can the C3 bit at the other end. So they can be on the same side or different sides. "same side" can't inter-convert to "different side" without breaking bonds. -
Satellite Clock adjustment to earth time, how is it done?
John Cuthber replied to Alan McDougall's topic in Relativity
If the GPS satellite's clock isn't giving a signal you can count what is it doing? I grant you that the way it does it it to multiply up a signal from the quartz clock to give a signal that is optimally attenuated by the Cs (or Rb) gas but, somewhere in that box of tricks is an electronic signal at 9GHz which I could count. If I had £500 to spare I could use this http://www.ebay.co.uk/itm/HP-5351B-Microwave-Frequency-Counter-26-5GHz-/140823102262?pt=UK_BOI_Electrical_Test_Measurement_Equipment_ET&hash=item20c9b60336#ht_500wt_1203 and get 11 digits I don't think NASA would have any trouble getting the other 2 digits needed to tell 10.22999999543 from 10.23 so I question the assertion that "you couldn't do it with the precision necessary anyway" In the end it's a philosophical point. If I lock a known fixed multiple 10MHz signal to the 9 Ghz then measure the 10MHz signal, have I measured the 9GHz signal? However, if I want the 1MHz to look like 1MHz from earth while the clock is in orbit, I have to change the multiplier one way or another because the 9GHz changes whether I like it or not. Does anyone have a schematic of the clock(s) they use? -
We already established that this assertion " anyone can make capital gains, rich or not." is false. We pointed out the counter examples and you even accepted them. Please don't try to re introduce false arguments. "There's a whole readily identified group of people who can't take the earned income credit either, is there a reason why this matters? " Who cares if it matters. The fact is that nobody was trying to claim that it wasn't true. The truth or falsehood of a statement that nobody made is a bit of a strawman isn't it.
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Satellite Clock adjustment to earth time, how is it done?
John Cuthber replied to Alan McDougall's topic in Relativity
For a start, I can get a 10 GHz counter from ebay. For a finish, I'm so glad I included the word primary in my earlier post. The fact remains that you don't change the frequency of the atomic clock, you alter the fraction of that frequency that you call 1Hz (or 10 MHz). BTW, where do you get a 10.2999.... Mhz quartz crystal from? Never mind the particular frequency- how do you get one with a frequency that's known to 12 digits or so? I'm pretty sure that, somewhere tucked away inside the computers that run these clocks is an adjustable constant which amounts to "How many do I count up to to get a second?" -
Satellite Clock adjustment to earth time, how is it done?
John Cuthber replied to Alan McDougall's topic in Relativity
Moot point. The rate of the (primary) oscillators is is indeed adjusted (from our point of view) by the fact that they are in low gravity and moving fast. And there's nothing you can do about that. It's an atomic clock- you don't get to choose the frequency. The satellites seem to keep time because the counters which on earth would say "when I count 9,192,631,770 ocillations, it's a second" are set up to count to a different number. I imagine that there was once a slightly odd discussion between Hewlett Packard and NASA something along the lines of NASA "You know those really nice atomic clocks you make? HP "Yes, what about them?" NASA " Can you make one that runs slow?" HP "£$%^* (unprintable)" NASA-"No, really, we want one that runs at the wrong speed on Earth so it keeps what looks like proper time while it's in space" -
plans for a lunar telescope are coming together
John Cuthber replied to Moontanman's topic in Science News
If you put it on the far side of the moon (why do people call it the dark side? Too much Pink Floyd perhaps) then the moon screens light and electrical noise coming from the Earth. Losing "earthshine" is potentially useful. -
So, what you meant by "Everyone can make capital gains, rich or not." was "not everyone can make capital gains and there's a whole readily identified group of people who can't because they are too poor". I hope you can understand why I got confused there. My other point is that only a little of my income is capital gains (on which I pay a reduced rate of tax) I pay normal income tax on pretty much the whole of my income. So my overall % tax is a bit less than the income tax rate. Poor Fred has practically no way to enjoy the benefit of low tax by getting part of his income via capital gains. On the other hand, Mr Rich gets more of his actual income from capital gains than through normal "income" so he pays the lowest percentage tax. I really don't think it's right that the poorest people generally end up paying the highest % tax. (Incidentally, Fred's neighbour, Bert, is even worse off than Fred. Bert's income is so low that he and his family get state benefits which are means tested. If Bert manages to get some sort of temporary job then half the money he gets is deducted from his social security cheque. Bert pays a marginal income tax rate of 50% on any extra money he earns.) We seem to have set up a perfectly inverted tax structure wher the less you earn, the more of it you pay. And it wasn't the poor guys who set that up. (I know I'm ignoring the tax thresholds, but the principle still stands. The tax thresholds don't matter to you if none of your income is treated as a salary because it's all paid to you in stock options and you only pay capital gains tax on it. Bert is still goosed anyway- no matter what the thresholds are.)
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I can cite at least on psychoactive drug that has no accessible UV absorption, so the question is moot. I also generally find that I can see blood perfectly well under normal visible light. The stuff is bright red. Also, the range from 200 to 400 nm covers pretty much the whole range of UV that's going to be any use at all. (longer than 400 and it's visible, shorter than 200 and it gets absorbed by oxygen in the air.) So this "200-400 nm: Forensic analysis, drug detection" is pretty meaningless. Add to that the fact that UV leds for wavelengths less than about 350nm are getting into the range of seriously expensive and you are probably on a hiding to nothing. What are you actually trying to achieve?
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It's easy to recognise websites that give competent medical advice. They tell you to go and see a doctor. So: go and see a doctor. However, in the meantime, it wouldn't do any harm to change the brand of band-aids you use and see if that helps. In answer to the original question: Taking any drug while healthy (for most definitions of healthy) is a bad idea to at least some extent. All drugs have side effects. (essentially all antibiotics are likely to upset your stomach) Also, widespread use of antibiotics is likely to lead to widespread resistance among bacteria which doesn't help anyone.
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It doesn't matter how "typical" it is. One person who can't make capital gains is enough to falsify the assertion that everyone can. I grant you that Fred is imaginary, but I don't think he's remotely implausible. Real "Freds" exist.
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OK, we can debate whether or not ParanoiA is poor but let's not bother. Lets consider Fred in stead. Fred lives in a run down bit of a city. He didn't do well at school. He knows that school wasn't that great but he also knows that he's just not that bright. On the other hand, he's lucky: he has a couple of jobs. The day job flipping burgers used to just about cover the bills but the prices went up a lot and minimum wage didn't. A friend of a friend put his name forward for a cleaning job and so he now does a few more hours a day. He's just about keeping his head above water. In fact, he even has some savings. He can put aside a little at the end of the month. But he knows that cash is earmarked. A while back- about the time he got the second job, Fred's dad died. A pity- but there was a slight silver lining. Dad left Fred some money. Not much- enough to buy a season ticket for the commute to his night time job. Fred knows that, if he doesn't have the cash to replace that ticket each year when it runs out he is stuffed. Fred has heard that there are jobs going in the next city along but he doesn't think much of the idea. For a start, he heard on the news that this recession is world wide so there's no way there will be many jobs for unskilled labour in that city, any more than there are lots in his town. Also, he knows that he was lucky to get his jobs where he is. If it hadn't been for that friend of a friend he'd be in trouble. Probably the same sort of trouble as his brother Joe. Joe went into the "recreational pharmaceuticals" business and, predictably, went to jail. So Fred is too scared to move to another town- and even if he wanted to the landlord would want a deposit and there's no way he can raise that. Also, he still has hopes of marrying his girlfriend though her dad has other ideas. He understands that well enough. Dad want's someone who can look after her well. And of course, while she's living at home with dad she's helping pay his rent. Still, there's one ray of hope in his life. He heard that some bloke called ParanoiA will tell him how he can make enough money from capital investments that he will have to pay tax on it. That looks like a pire dream now. Well Paranoia: over to you. How does the story end? (And no lottery tickets)