To elaborate on "i kan reed" 's not incorrect answer,
We'll leave aside the "sucked in" bit of it. Your physics course will teach you eventually that most (all?) fields are of infinite extent, though equally, they get weaker with separation between the bodies pretty rapidly. You can also neglect the mass of the object - the greater the mass, the greater the forces produced which precisely counteracts the effect of the greater mass. (If the counteracting isn't exact, there's a Noble or several for the person who proves it ; smart people have tried, and not yet succeeded.) Let's just pretend you'd asked a better defined question such as "how slow does it have to be going to be captured into an orbit by the Earth".
Well, now you have to contend with the fact that both the asteroid and the Earth are travelling in the Sun's gravitational field. And in a Sun-centred frame of reference the Earth is travelling at about (2 * pi * 150million) km/year = 107515 km/hour around the Sun (plus or minus several percent because it's orbit isn't circular). But there's nothing in the question you pose to describe if the asteroid is travelling in the same direction as the Earth, in the opposite direction. If the two are travelling in the same direction, then you can achieve low closing velocities (which is what you probably really mean by "how slow") ; but if they're in contra-directional orbits, then they're going to have at least the closing velocity of the Earth around it's solar orbit (in which case, the asteroid will have to be coming from close to the Sun, and just stalling near the Earth's orbit, just as the Earth is coming past, to pick it up out of solar-dominated motion to being in an Earth-dominated domain of orbital parameters.
Then you have to look at how close the asteroid gets to Earth ; if you allow it to aerobrake in the atmosphere, you can dump a lot of velocity and momentum there, to allow the object to be captured into Earth orbit. It can happen, but it's pretty delicate - there are several craters on Mars and Venus (IIRC) from when such manoeuvres didn't go to plan.
It's not an unreasonable question, but the topic is more complex than you seem to appreciate in your posing of the question.
You were probably doing it wrong. Did you have your arm shaved? Bad move. Did you hold your arm in the liquid nitrogen for several minutes, as opposed to pouring a bucket of LN2 over your arm? They are two very different events.
I can assure you that the Leidenfrost effect works perfectly well - when I was casting lead weights for diving, I had my sand moulds a little too damp - cue bubbling splashing lead, with substantial gobbets of molten lead splashing over my arm - around 230degC temperature difference. It hurt, that's for sure ; but it would have hurt a damned sight more if not for the Leidenfrost effect.
The scars have nearly disappeared now. Or been over-printed by other cuts, nicks and abrasions. Only took 25 years.
By the time you get to studying functions - about age 14 when I was in school, you automatically have to learn how to sketch graphs just by reading the function. In fact, sketching them, by hand, was a small but significant number of marks in maths papers, including labelling them with (as appropriate), the expressions for where they cross the axes, inversion and inflexion points. That's the expressions, not the values. The expressions that you obtain by algebraically manipulating the function. i.e., by doing the actual mathematics.
Can someone actually provide me a link to examples that require you to use these machines? Real exam questions.
I find it pretty unlikely, a priori, that it would actually be quicker to set up the problem on a "graphing calculator" and then transfer the results onto your manuscript, compared to just writing it out directly on your manuscript. Plus, of course, you get the possible marks for showing your working.
OK ; maybe I'm old school - if I need a square root and I don't have a calculator or log tables to hand, I just Newton-Raphson until I've got the necessary number of significant digits. If I can't just get the root by inspection. It's not exactly rocket science.
Oh well, I guess the Elite clone (oolite, www.oolite.org or something like that ; it's blocked here because it appears on some blacklist as a games site) that I use to waste my time between finishing work and going to sleep must be positivley fossilized then.
But it does nothing to change the fact that he and both of his successors left office after being "suddenly taken ill",
Did you actually pay any attention to the events as they were happening? I rather suspect not.
How can I put this? The dead dogs in the gutter in Nowhereville, Saskatchewan knew that Chernenko and Andropov were "Norwegian Blue" placements. Even, incredible as it seems, Raygun the Retard, knew.
recall redng abut it in the New Scentist at the time. There was much puzzlement, but the alerts from Sweden were notcoming from nuclear reactors etc, but out of academia, who have no reasn to keep things in-house while they figure out waht was going on.
If you look at a map, Sweden was probably the closest country to Chernobyl outside the Soviet block. There was no "Ukraine", "Belarus" or Baltic states then , they were all Oblasts or Okrugs of the USSR. (Possibly parts of Finland were closer ; I'd need a map to check.)
The wind took the cloud NW from Chernobyl to th Baltic, then W across the North Sea, leading to high deposition rates over the Hiighlands of Scotland and the English Lake District (I had to check radiation levels as part of my rsk assessment for mapping work in the Highlands 2 years later ; sale of sheep for food was still banned at that time, but since I was a veggie, that didn't fuss me). It was several days later that the main plume swept back across central Europe.
It's possible that places like nuclear reactors and research stations picked up the cloud earlier, using their more sensitive detectors, but they weren't reporting it until after the other news had broken and they could say "It's not us!"
our (catholic) religious education teacher not willing to believe that the steam exiting the cooling tower of a nuclear power plant is not actually a radioactive smoke plume
Why would you be listening to a RE teacher about a science topic. You might as well ask a self-professed celibate virgin about the pleasures of buggering little boys.
Finding plants that concentrate this stuff would be most valuable.
If the cost of preparing the land and harvesting the crops for decades (you're not going to get everything in one cycle) turns out to be cheaper than just letting the radioactivity decay....
Which might be true, bit it's by no means a certainty.
Actually, the radiation cloud was first detected (in the West ; Pripyat knew about it a couple of day's earlier. My wife was working out of doors a hundred or so kilometres away for the week afterwards ; we paid attention to the details when she came to the west with me) over southern Sweden, from where it spread to Northern Britain and then worked it's way south. Germany and Austria were several days later. They were hit, undoubtedly, but the winds delayed the arrival of the radiation cloud for several days.
It's not impossible that the two are related (I got stuck in the Heathrow Fiasco for several days. Pain in the arse.), but I'm not aware of any strong evidence to link the two events.
DDT is fat soluble not water soluble, and very slow to break down. Caesium (Cs-137) and Iodine (I-127, IIRC), the main radio-nucleotides released by Chernobyl, are moderately to very water soluble, and have small, (decades) half lives. Which makes bio-accumulation much less of an issue. Not "no issue", but not much of an issue.
The radiation cloud came over ; the rain fell, bringing the fallout with it ; the radio-nucleotides were washed out of the sky and into the soil, and are slowly working through the soil to rivers and streams (delayed by absorption on to plant debris, soil minerals and humic acids). Give it another couple of centuries and there won't be a problem. In Germany.
No planes fell out of the sky, it's true. However a lot of things did happen. Planes were cancelled. Helicopters for access to offshore oil installations were grounded (I was stuck for 9 days like this ; on the last day we got permission to change personnel by boat, and the next day the flying ban was lifted). The small number of appropriate atmospheric monitoring stations did detect appreciable amounts of gas.
The problem was that engine manufacturers hadn't specified levels of airborne ash below which it was considered safe to run their engines, because they hadn't done the appropriate tests, because no one had asked them to document this aspect of their behaviour. So, nobody knew (to the degree that they were willing to risk killing several hundred of their passengers in an experiment) whether or not it was safe to fly. And caution ruled.
Look at what is happening to Malaysian Airlines after two crashes in a few months. One we just don't know what happened ; the other is in no way MA's fault (given normal airline practice at the time). But that's not stopping them from going bust, their staff being laid off, andeveryone suffering.
Do you have the balls (or cunt, if you're anatomically female) to take the risk of destroying your company? Oh, sorry, dumb question ; you're an AC ; of course you don't have the balls (or cunt) to back up your carping.
From Microsoft's chair, they have no choice but to fight this - how many non-US countries and corporations are going to subscribe to Office365 and other MS-cloud services if it's publicly known that MS will give your information to a foreign government?
I agree with your logic. But NOSANE organisation is going to use a system that requires them to store confidential data in any location other than on their own servers.
Which doesn't preclude there being many insane, or foolish, or bamboozled, organisations out there.
I recall that Google did a line of "Google-in-a-box" servers a while ago that would plug into your (intra-)network and would go off to index it (configurable), but keep the index physically in your data centre. I wouldn't be surprised if Micro$loth had done something similar with Orifice365 - a local server which your (intra-)net users log into, but might get patches etc from a MS server on a configurable schedule.
cough syrup is meant to do diddly squat. It's a placebo. It comes in bottles, can taste nasty or horrible, and is a bright colour . All perfect placebo packaging. Possibly a very slight dose of topical painkiller for the throat, but otherwise, diddly squat.
OTOH, it could be that the mortality rate is within the expected bounds (1 in 2 to 3 in 4 ) and that a lot of people are getting infected and dieing away from the areas that the forces of the state can get to, to count the living and the dead.
When the human testing starts, should it be old people first? afftected-continent people first? family-receives-high-payment people first?
Trolls first.
I think they should be volunteers at the very least.
Your application as a volunteer has been accepted. Your Ebola infection should shortly be delivered and the drugs (or placebo ; not your choice which you get) will be delivered in 10 days time, by when you should have started to develop symptoms. Please take it to a nearby clinic and pay someone to inject you. Your anonymity will, of course, be protected by us, though we cannot speak for every other person you meet, including the taxi driver who takes you to the clinic.
Go back and re-read my post. I only mention a dark sky as a sideline.
You can have a sky utterly devoid of light pollution and iit still be utterly useless for astronomy by dint of driving rain or scudding cloud, even withut the precipitation. With around 2/3 of nights unusable, that is the main reason that I shipped my telescope off to my sister's country guest house. On those rare occasions that it does get used, it`s much better there than in my home town. But that`s still only a few nights a year that it gets used.
Going back to the original question - what is the most effective use for getting kids interested in astronomy (or whatever the Q was - I can't remember now) - then choosing your time and place is going to be important. Making a big build up and then being washed out by the rain (or snow, or in high summer, fog) is going to be more effective dampener than taking an opportunity of good conditions and using it there and then.
"Civlisation - I buy it with my taxes!" Or some failry similar quote. There used to bwe a regular on here who used it in his signature. I can't remember if it was a Robert Heinlein or Thomas Paine quote, but it was someone who you wouldn't normally expect such thoughts from.
Use lots of smaller poles and make it really roll like a cylinder.
You'd get into a law of diminishing returns in rolling resistance compared to the complexity of the modification. You could probably turn the octagonal section of the modified (cuboid) block into a dodecagonal section by using rods of two or three different diameters and lashed into (their term) "mats" before being lashed onto the block. But whether it would be as stable, is one very open question ; whether it would be as strong under cornering (which would preferentially load the thinnest rods in the "mat") as the octagonal-section / dodecahedral-enveloped system that is proposed here.
Hmmm, I'm trying to remember my crystallographic space groups. Dodecahedra are in the same space group (class) as cubes (it's the secondary axes of 3-fold rotational symmetry that matter), so by choosing the arrangement of rods in the mat you should be able to make the envelope into a true (Platonic) dodecahedron envelope. Contrary to the paper's illustration, you'd need to attach three trios of "rods" to the three pairs of faces so that the ends of the rods protrude over the faces of the (cubic) core. And you'd need two different lengths of rods, to round off the corners. And I'm falling into exactly the same "diminishing returns" trap that I'm pointing out under your feet.
There's some interesting geometry there. And since I'm sharing an office with a lifting-slinging-hoisting-crane operations instructor, I think I'll shove that paper under his nose because he likes fiddling with scraps of rope (a "marlinspike seaman" as they were called in my youth), and I think he'll be interested.
It's an interesting idea. But it does clearly contradict the evidence of the contemporary records, which is a BIG strike against it being true.
Substituting EVD (Ebola Virus Disease) for HIV/ SIV, and bats for primates... and you've got a good description of the probable source mechanism of the current Ebola outbreaks in West and Central Africa.
Incidentally, "improper animal handling procedures resulting in blood-to-blood contact" may include chopping up an infected animal for dinner (as most people envisage it), or digging bits of splattered bat out of the radiator of your car or from your clothing after the bat has become road kill. Which is certainly what worries us and our medical advisers as we travel near to infected areas.
Slashdot Mirror
We'll leave aside the "sucked in" bit of it. Your physics course will teach you eventually that most (all?) fields are of infinite extent, though equally, they get weaker with separation between the bodies pretty rapidly. You can also neglect the mass of the object - the greater the mass, the greater the forces produced which precisely counteracts the effect of the greater mass. (If the counteracting isn't exact, there's a Noble or several for the person who proves it ; smart people have tried, and not yet succeeded.) Let's just pretend you'd asked a better defined question such as "how slow does it have to be going to be captured into an orbit by the Earth".
Well, now you have to contend with the fact that both the asteroid and the Earth are travelling in the Sun's gravitational field. And in a Sun-centred frame of reference the Earth is travelling at about (2 * pi * 150million) km /year = 107515 km/hour around the Sun (plus or minus several percent because it's orbit isn't circular). But there's nothing in the question you pose to describe if the asteroid is travelling in the same direction as the Earth, in the opposite direction. If the two are travelling in the same direction, then you can achieve low closing velocities (which is what you probably really mean by "how slow") ; but if they're in contra-directional orbits, then they're going to have at least the closing velocity of the Earth around it's solar orbit (in which case, the asteroid will have to be coming from close to the Sun, and just stalling near the Earth's orbit, just as the Earth is coming past, to pick it up out of solar-dominated motion to being in an Earth-dominated domain of orbital parameters.
Then you have to look at how close the asteroid gets to Earth ; if you allow it to aerobrake in the atmosphere, you can dump a lot of velocity and momentum there, to allow the object to be captured into Earth orbit. It can happen, but it's pretty delicate - there are several craters on Mars and Venus (IIRC) from when such manoeuvres didn't go to plan.
It's not an unreasonable question, but the topic is more complex than you seem to appreciate in your posing of the question.
I can assure you that the Leidenfrost effect works perfectly well - when I was casting lead weights for diving, I had my sand moulds a little too damp - cue bubbling splashing lead, with substantial gobbets of molten lead splashing over my arm - around 230degC temperature difference. It hurt, that's for sure ; but it would have hurt a damned sight more if not for the Leidenfrost effect.
The scars have nearly disappeared now. Or been over-printed by other cuts, nicks and abrasions. Only took 25 years.
Can someone actually provide me a link to examples that require you to use these machines? Real exam questions.
I find it pretty unlikely, a priori, that it would actually be quicker to set up the problem on a "graphing calculator" and then transfer the results onto your manuscript, compared to just writing it out directly on your manuscript. Plus, of course, you get the possible marks for showing your working.
OK ; maybe I'm old school - if I need a square root and I don't have a calculator or log tables to hand, I just Newton-Raphson until I've got the necessary number of significant digits. If I can't just get the root by inspection. It's not exactly rocket science.
And ... so?
Did you actually pay any attention to the events as they were happening? I rather suspect not.
How can I put this? The dead dogs in the gutter in Nowhereville, Saskatchewan knew that Chernenko and Andropov were "Norwegian Blue" placements. Even, incredible as it seems, Raygun the Retard, knew.
If you look at a map, Sweden was probably the closest country to Chernobyl outside the Soviet block. There was no "Ukraine", "Belarus" or Baltic states then , they were all Oblasts or Okrugs of the USSR. (Possibly parts of Finland were closer ; I'd need a map to check.)
The wind took the cloud NW from Chernobyl to th Baltic, then W across the North Sea, leading to high deposition rates over the Hiighlands of Scotland and the English Lake District (I had to check radiation levels as part of my rsk assessment for mapping work in the Highlands 2 years later ; sale of sheep for food was still banned at that time, but since I was a veggie, that didn't fuss me). It was several days later that the main plume swept back across central Europe.
It's possible that places like nuclear reactors and research stations picked up the cloud earlier, using their more sensitive detectors, but they weren't reporting it until after the other news had broken and they could say "It's not us!"
Why would you be listening to a RE teacher about a science topic. You might as well ask a self-professed celibate virgin about the pleasures of buggering little boys.
Oh. Sorry.
Preparation H?
You can get vitamin D (and it's precursors) in edible form too.Many fresh veg, fish ... various other dietary sources. Not just sunlight.
If the cost of preparing the land and harvesting the crops for decades (you're not going to get everything in one cycle) turns out to be cheaper than just letting the radioactivity decay ....
Which might be true, bit it's by no means a certainty.
Correct, but pointfull?
It's not impossible that the two are related (I got stuck in the Heathrow Fiasco for several days. Pain in the arse.), but I'm not aware of any strong evidence to link the two events.
DDT is fat soluble not water soluble, and very slow to break down. Caesium (Cs-137) and Iodine (I-127, IIRC), the main radio-nucleotides released by Chernobyl, are moderately to very water soluble, and have small, (decades) half lives. Which makes bio-accumulation much less of an issue. Not "no issue", but not much of an issue.
The radiation cloud came over ; the rain fell, bringing the fallout with it ; the radio-nucleotides were washed out of the sky and into the soil, and are slowly working through the soil to rivers and streams (delayed by absorption on to plant debris, soil minerals and humic acids). Give it another couple of centuries and there won't be a problem. In Germany.
The problem was that engine manufacturers hadn't specified levels of airborne ash below which it was considered safe to run their engines, because they hadn't done the appropriate tests, because no one had asked them to document this aspect of their behaviour. So, nobody knew (to the degree that they were willing to risk killing several hundred of their passengers in an experiment) whether or not it was safe to fly. And caution ruled.
Look at what is happening to Malaysian Airlines after two crashes in a few months. One we just don't know what happened ; the other is in no way MA's fault (given normal airline practice at the time). But that's not stopping them from going bust, their staff being laid off, andeveryone suffering.
Do you have the balls (or cunt, if you're anatomically female) to take the risk of destroying your company? Oh, sorry, dumb question ; you're an AC ; of course you don't have the balls (or cunt) to back up your carping.
"Putin" is less than 10 letters long.
I agree with your logic. But NO SANE organisation is going to use a system that requires them to store confidential data in any location other than on their own servers.
Which doesn't preclude there being many insane, or foolish, or bamboozled, organisations out there.
I recall that Google did a line of "Google-in-a-box" servers a while ago that would plug into your (intra-)network and would go off to index it (configurable), but keep the index physically in your data centre. I wouldn't be surprised if Micro$loth had done something similar with Orifice365 - a local server which your (intra-)net users log into, but might get patches etc from a MS server on a configurable schedule.
IT worked perfectly, you mean?
cough syrup is meant to do diddly squat. It's a placebo. It comes in bottles, can taste nasty or horrible, and is a bright colour . All perfect placebo packaging. Possibly a very slight dose of topical painkiller for the throat, but otherwise, diddly squat.
Or get tissue (including blood) into a wound on the human, when skinning / gutting / butchering a carcass killed for meat.
OTOH, it could be that the mortality rate is within the expected bounds (1 in 2 to 3 in 4 ) and that a lot of people are getting infected and dieing away from the areas that the forces of the state can get to, to count the living and the dead.
Trolls first.
I think they should be volunteers at the very least.
Your application as a volunteer has been accepted. Your Ebola infection should shortly be delivered and the drugs (or placebo ; not your choice which you get) will be delivered in 10 days time, by when you should have started to develop symptoms. Please take it to a nearby clinic and pay someone to inject you. Your anonymity will, of course, be protected by us, though we cannot speak for every other person you meet, including the taxi driver who takes you to the clinic.
You can have a sky utterly devoid of light pollution and iit still be utterly useless for astronomy by dint of driving rain or scudding cloud, even withut the precipitation. With around 2/3 of nights unusable, that is the main reason that I shipped my telescope off to my sister's country guest house. On those rare occasions that it does get used, it`s much better there than in my home town. But that`s still only a few nights a year that it gets used.
Going back to the original question - what is the most effective use for getting kids interested in astronomy (or whatever the Q was - I can't remember now) - then choosing your time and place is going to be important. Making a big build up and then being washed out by the rain (or snow, or in high summer, fog) is going to be more effective dampener than taking an opportunity of good conditions and using it there and then.
"Civlisation - I buy it with my taxes!" Or some failry similar quote. There used to bwe a regular on here who used it in his signature. I can't remember if it was a Robert Heinlein or Thomas Paine quote, but it was someone who you wouldn't normally expect such thoughts from.
If only Nature hadn't put it at the bottom of a 5.4 Earth-mass gravity hole. that's almost as malicious as your average god.
OTOH, finding a computer you can use the model-M on in another decade may be harder.
You'd get into a law of diminishing returns in rolling resistance compared to the complexity of the modification. You could probably turn the octagonal section of the modified (cuboid) block into a dodecagonal section by using rods of two or three different diameters and lashed into (their term) "mats" before being lashed onto the block. But whether it would be as stable, is one very open question ; whether it would be as strong under cornering (which would preferentially load the thinnest rods in the "mat") as the octagonal-section / dodecahedral-enveloped system that is proposed here.
Hmmm, I'm trying to remember my crystallographic space groups. Dodecahedra are in the same space group (class) as cubes (it's the secondary axes of 3-fold rotational symmetry that matter), so by choosing the arrangement of rods in the mat you should be able to make the envelope into a true (Platonic) dodecahedron envelope. Contrary to the paper's illustration, you'd need to attach three trios of "rods" to the three pairs of faces so that the ends of the rods protrude over the faces of the (cubic) core. And you'd need two different lengths of rods, to round off the corners. And I'm falling into exactly the same "diminishing returns" trap that I'm pointing out under your feet.
There's some interesting geometry there. And since I'm sharing an office with a lifting-slinging-hoisting-crane operations instructor, I think I'll shove that paper under his nose because he likes fiddling with scraps of rope (a "marlinspike seaman" as they were called in my youth), and I think he'll be interested.
It's an interesting idea. But it does clearly contradict the evidence of the contemporary records, which is a BIG strike against it being true.
Incidentally, "improper animal handling procedures resulting in blood-to-blood contact" may include chopping up an infected animal for dinner (as most people envisage it), or digging bits of splattered bat out of the radiator of your car or from your clothing after the bat has become road kill. Which is certainly what worries us and our medical advisers as we travel near to infected areas.