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 5th October 2016, 02:44 PM #241 John Nowak Graduate Poster   Join Date: May 2014 Location: Tampa, FL Posts: 1,806 Originally Posted by Dave Rogers No, I think I see how it works, and why it doesn't. So because he wants to avoid subtracting when he wants to work with numbers less than one, he subtracts on all numbers less than one? That's unnecessary, unworkable, and probably insane. I think you're right. __________________ >Reason being is that you guys appear to have absolutely no field experience in listening for invisible people in the forest. I do. -historian
 5th October 2016, 07:59 PM #242 jaydeehess Penultimate Amazing     Join Date: Nov 2006 Location: 40 miles north of the border Posts: 20,843 Originally Posted by John Nowak I Thus, 3n126 = 0.00126, (126 x 10^-3) and 3p251 is 10^3 x 2.51 =2510. . .000126 is not 126 X 10-3 It is 1.26X10-4 or 126 X10-6 I read 3n251 as indeed 251X10-3 = 0.251 3p126 I read as 126X103=251000 But if I am simply reading it wrong , I believe I am still correct in it's not being "less complicated", and that introducing letters into numbers will just make algebra even more flummoxing to high school students.
 5th October 2016, 08:23 PM #243 jaydeehess Penultimate Amazing     Join Date: Nov 2006 Location: 40 miles north of the border Posts: 20,843 Originally Posted by Dave Rogers No, I think I see how it works, and why it doesn't. He notates negative exponents from 1 to 9 by subtracting the exponent from 10, from 10 to 99 by subtracting it from 100, from 100 to 990 by subtracting it from 1000, ... The result is that you can multiply by simply adding exponents and then dropping a leading 1; except that sometimes you have to multiply by adding exponents and not dropping the leading 1. There will be a rule determining which you have to do, but that adds an operation that isn't necessary with traditional scientific notation, so at best his notation adds one extra step. This is a result of his idea that, for a negative exponent, any number of leading 9s may be discarded; unfortunately, that idea simply doesn't work infallibly. Dave What? Thats lunacy, even more unecessarily complicated than I thought it was supposed to work.
 5th October 2016, 08:38 PM #244 Jrrarglblarg Guest   Join Date: Nov 2010 Posts: 12,673 Originally Posted by jaydeehess The issue reminds me of a problem in survival training here in the north. Specifically on the matter of building s snow hut shelter. I have heard it said that these are warmer than the ambient air temps because snow is frozen water which solidifies at zero C. So the interior can't be colder than that. No, its warmer because snow is a good insulator and the ground below the hut is warmer than the air above the snow. Heat comes from the earth. When I hear this I marvel that we can build steel buildings that don't heat people to death. After all steel solidifies at a bit above 1300C and cannot be colder than that. The problem is, that's not why snow shelters are warmer than ambient, and your explanation differs from all other versions I've ever heard, because it's wrong. Ground temp won't contribute anything, because the frost line is 30 inches below the surface, minimum. The correct explanation is that the interior of the snow cave can be warmed all the way up to the freezing point of water, which can be very much warmer than ambient. Thus, steel buildings cannot be warmed to greater than the melting point of steel.
 6th October 2016, 01:02 AM #245 Dave Rogers Bandaged ice that stampedes inexpensively through a scribbled morning waving necessary ankles     Join Date: Jan 2007 Location: Cair Paravel, according to XKCD Posts: 32,935 Originally Posted by John Nowak I'll give him this: it avoids the use of superscripts and the repetitive "x 10^" that we're presently struck with. You can type it out in Notepad. Also not a real advantage. These days, using the letter e to replace "x 10^" is pretty much universal, courtesy of Excel. So, for example, 6.626e-34 is not significantly harder to type than 66n6626 - two extra characters not requiring shift or control keys - and its actual magnitude is much clearer. Dave __________________ There is truth and there are lies. - President Joseph R. Biden, January 20th, 2021
 6th October 2016, 02:40 AM #246 sts60 Illuminator     Join Date: Jul 2007 Posts: 3,767 Originally Posted by Jrrarglblarg Thus, steel buildings cannot be warmed to greater than the melting point of steel. Well, they can, but they're not very buildingy by then.
 6th October 2016, 06:01 AM #247 jaydeehess Penultimate Amazing     Join Date: Nov 2006 Location: 40 miles north of the border Posts: 20,843 Originally Posted by Jrrarglblarg The problem is, that's not why snow shelters are warmer than ambient, and your explanation differs from all other versions I've ever heard, because it's wrong. Ground temp won't contribute anything, because the frost line is 30 inches below the surface, minimum. The correct explanation is that the interior of the snow cave can be warmed all the way up to the freezing point of water, which can be very much warmer than ambient. Thus, steel buildings cannot be warmed to greater than the melting point of steel. Snow shelter construction. -pick an area at least twice the diameter of the finished shelter -use shovel or snowshoe to mix up the snow on the ground and pile it up in the area where you want the finished shelter to be. -Make coffee, sing take pictures,,, whatever, for at least an hour -dig an entrance and hollow out the pile. The turning and piling will have mixed up different temp layers of snow, the outer foot solidifies. - the interior will always be warmer than the exterior(once you have put a snow block door in place) even if there are no people in it or candles burning. Heat has to come from somewhere and it isn't the ambient air. Yes, the addition of people and/or candles(making sure there are air holes in the sides and top of the shelter) will warm it up to the point of the melting of water. Slept in a few myself when I was young and invincible. Last edited by jaydeehess; 6th October 2016 at 06:03 AM.
 6th October 2016, 06:06 AM #248 jaydeehess Penultimate Amazing     Join Date: Nov 2006 Location: 40 miles north of the border Posts: 20,843 Originally Posted by jaydeehess .000126 is not 126 X 10-3 It is 1.26X10-4 or 126 X10-6 I read 3n251 as indeed 251X10-3 = 0.251 3p126 I read as 126X103=251000 But if I am simply reading it wrong , I believe I am still correct in it's not being "less complicated", and that introducing letters into numbers will just make algebra even more flummoxing to high school students. tee hee
 6th October 2016, 07:15 AM #249 John Nowak Graduate Poster   Join Date: May 2014 Location: Tampa, FL Posts: 1,806 Originally Posted by jaydeehess .000126 is not 126 X 10-3 Minor glitch: I said 0.00126, not .000126. I believe his mantissa is always a number less than 10; there's an implied decimal after the 1. Thus, 1.26 x 10-3. __________________ >Reason being is that you guys appear to have absolutely no field experience in listening for invisible people in the forest. I do. -historian
 6th October 2016, 07:21 AM #250 John Nowak Graduate Poster   Join Date: May 2014 Location: Tampa, FL Posts: 1,806 Originally Posted by Dave Rogers Also not a real advantage. These days, using the letter e to replace "x 10^" is pretty much universal, courtesy of Excel. So, for example, 6.626e-34 is not significantly harder to type than 66n6626 - two extra characters not requiring shift or control keys - and its actual magnitude is much clearer. Dave I'm in full agreement. __________________ >Reason being is that you guys appear to have absolutely no field experience in listening for invisible people in the forest. I do. -historian
 6th October 2016, 08:10 AM #251 JayUtah Penultimate Amazing     Join Date: Sep 2011 Location: The great American West Posts: 20,936 Originally Posted by ArmillarySphere So veering into the actual physics/engineering, how much of the heat is taken up by the surrounding air and how much goes into the ablative material's phase transition from solid to plasma? The document I thought had the actual numbers in it, didn't. Let me pick through my library.
 6th October 2016, 08:14 AM #252 jaydeehess Penultimate Amazing     Join Date: Nov 2006 Location: 40 miles north of the border Posts: 20,843 Originally Posted by John Nowak I believe his mantissa is always a number less than 10; there's an implied decimal after the 1. Thus, 1.26 x 10-3. Like I said "less" confusing???? Now we just imply where the decimal point is supposed to be, and that whole hot mess that deals with numbers smaller than zero, and have a good percentage more high school students run away from science and engineering because we not only use letters for variables but also introduce a couple into numbers themselves. Hell, compared to this idiotic number notation, understanding the dissipation of heat in re-entry vehicles is easy-peasy.
 6th October 2016, 08:18 AM #253 jaydeehess Penultimate Amazing     Join Date: Nov 2006 Location: 40 miles north of the border Posts: 20,843 Originally Posted by ArmillarySphere So veering into the actual physics/engineering, how much of the heat is taken up by the surrounding air and how much goes into the ablative material's phase transition from solid to plasma? Originally Posted by JayUtah The document I thought had the actual numbers in it, didn't. Let me pick through my library. Let me guess though that it's a damn sight less than goes into raising the temperature of the spacecraft? To this non-engineer one thing is quite obvious, the air below the capsule is not static, it heats up and flows away to be replaced by cooler air. A torch would be the opposite, it heats up gases that are then directed to an object, those gases may flow away but are being replaced by more, previously heated gases
 6th October 2016, 08:33 AM #254 JayUtah Penultimate Amazing     Join Date: Sep 2011 Location: The great American West Posts: 20,936 Originally Posted by jaydeehess ..the air below the capsule is not static, it heats up and flows away to be replaced by cooler air. Yes, there is a convective component to the model. There is also a radiant component whereby the heated atmospheric gas applies heat to the heat shield via infrared. That's part of the brilliance of the design: the gases produced in the ablation process are substantially opaque to infrared. This principle is also applied in ablative linings for rocket nozzles.
 6th October 2016, 09:11 AM #255 John Nowak Graduate Poster   Join Date: May 2014 Location: Tampa, FL Posts: 1,806 Originally Posted by jaydeehess Like I said "less" confusing???? True enough. Look how hard it was to figure it out. __________________ >Reason being is that you guys appear to have absolutely no field experience in listening for invisible people in the forest. I do. -historian
 6th October 2016, 09:21 AM #256 JayUtah Penultimate Amazing     Join Date: Sep 2011 Location: The great American West Posts: 20,936 Originally Posted by John Nowak True enough. Look how hard it was to figure it out. I predict that Wogoga, if he responds at all to this critique of his system, will just say you're obviously not mathematically competent and can't see the genius inherent in his invention.
 6th October 2016, 09:24 AM #257 jaydeehess Penultimate Amazing     Join Date: Nov 2006 Location: 40 miles north of the border Posts: 20,843 Originally Posted by JayUtah Yes, there is a convective component to the model. There is also a radiant component whereby the heated atmospheric gas applies heat to the heat shield via infrared. That's part of the brilliance of the design: the gases produced in the ablation process are substantially opaque to infrared. This principle is also applied in ablative linings for rocket nozzles. I did not mean to imply that convection was the only or even primary form of heat transfer. However, to any layman it is the most obvious. Have a too hot cup of coffee, blow on it. Blow more air on it faster and see the temp lower faster. The ablative process should be fairly obvious to any science minded lay person as well. It takes heat to cause something to change phase. When we boil water the temp of the water does not go up beyond that of its boiling point which is why boiling is called a low temperature cooking process. It is also why altitude affects cooking time when boiling (a matter fully understood and taught in Home Economics classes when I was a kid) The steam produced can otoh be raised well above the temp of boiling water. So yeah, I also see that heating a heat shield to the point that causes it to become a gas will mean that the still solid part of that shield cannot yet be above its phase change temp.
 6th October 2016, 09:27 AM #258 jaydeehess Penultimate Amazing     Join Date: Nov 2006 Location: 40 miles north of the border Posts: 20,843 Originally Posted by John Nowak True enough. Look how hard it was to figure it out. I still don't get it,,, thought I did,,, nope apparently I don't. otoh I recall having absolutely no trouble at all when I was 12-13 years old and being taught scientific notation. It Made Sense Hell, significant digits was harder. Maybe it's just because I am a Canuck, you know, American Light.
 6th October 2016, 09:32 AM #259 John Nowak Graduate Poster   Join Date: May 2014 Location: Tampa, FL Posts: 1,806 Originally Posted by JayUtah I predict that Wogoga, if he responds at all to this critique of his system, will just say you're obviously not mathematically competent and can't see the genius inherent in his invention. No bet; you're probably correct. __________________ >Reason being is that you guys appear to have absolutely no field experience in listening for invisible people in the forest. I do. -historian
 6th October 2016, 09:33 AM #260 Dave Rogers Bandaged ice that stampedes inexpensively through a scribbled morning waving necessary ankles     Join Date: Jan 2007 Location: Cair Paravel, according to XKCD Posts: 32,935 Originally Posted by JayUtah I predict that Wogoga, if he responds at all to this critique of his system, will just say you're obviously not mathematically competent and can't see the genius inherent in his invention. Yeah, I obviously had to wing it in maths to get my doctorate in physics. Dave __________________ There is truth and there are lies. - President Joseph R. Biden, January 20th, 2021
 6th October 2016, 09:34 AM #261 John Nowak Graduate Poster   Join Date: May 2014 Location: Tampa, FL Posts: 1,806 Originally Posted by jaydeehess I still don't get it,,, thought I did,,, nope apparently I don't. I wouldn't be too worried about it - I'm intrigued by nomenclature, so it was fun for me to play with. But "not getting it?" I don't blame you. It's a silly notation system notably inferior to the ones in use. __________________ >Reason being is that you guys appear to have absolutely no field experience in listening for invisible people in the forest. I do. -historian
 6th October 2016, 09:36 AM #262 John Nowak Graduate Poster   Join Date: May 2014 Location: Tampa, FL Posts: 1,806 Originally Posted by Dave Rogers Yeah, I obviously had to wing it in maths to get my doctorate in physics. Mainstream cult physics, without a doubt. I got the physics reward in my high school; never was able to grasp the math behind quantum mechanics. __________________ >Reason being is that you guys appear to have absolutely no field experience in listening for invisible people in the forest. I do. -historian
 6th October 2016, 10:00 AM #263 JayUtah Penultimate Amazing     Join Date: Sep 2011 Location: The great American West Posts: 20,936 Originally Posted by John Nowak Mainstream cult physics, without a doubt. Yup, brainwashed by the Powers That Be. I've literally had hoax theorists tell me the entire engineering profession has been brainwashed by folks answering to NASA, for decades now. That's why the entire mainstream engineering profession accepts Apollo as real when it "clearly" isn't.
 6th October 2016, 10:07 AM #264 Jrrarglblarg Guest   Join Date: Nov 2010 Posts: 12,673 Quote: the interior will always be warmer than the exterior(once you have put a snow block door in place) even if there are no people in it or candles burning. Citation, please.
 6th October 2016, 10:36 AM #265 jaydeehess Penultimate Amazing     Join Date: Nov 2006 Location: 40 miles north of the border Posts: 20,843 Originally Posted by Dave Rogers Yeah, I obviously had to wing it in maths to get my doctorate in physics. Dave Originally Posted by John Nowak I wouldn't be too worried about it - I'm intrigued by nomenclature, so it was fun for me to play with. But "not getting it?" I don't blame you. It's a silly notation system notably inferior to the ones in use. I had no trouble getting my college diploma in electronic technology. But that was in the 80s, after all its not like designing a cct requires doing math. Nah, just insert various value components until you get operation something like what you had in mind.
 6th October 2016, 10:39 AM #266 jaydeehess Penultimate Amazing     Join Date: Nov 2006 Location: 40 miles north of the border Posts: 20,843 Originally Posted by Jrrarglblarg Citation, please. Citing my personal experience. We would leave the hut, go ice fishing for hours, come back and the hut interior was warmer than exterior air.
 6th October 2016, 11:01 AM #267 Jrrarglblarg Guest   Join Date: Nov 2010 Posts: 12,673 Originally Posted by jaydeehess Citing my personal experience. We would leave the hut, go ice fishing for hours, come back and the hut interior was warmer than exterior air. Numberless anecdote rejected. The soil maintains a constant temperature of roughly 50 degrees F, but way below the surface. There are laws and building codes for how deep posts and pilings need to be sunk, for that reason. Fence or sign posts that are set too shallow tend to get shoved up out of the soil by the action of freezing water expanding. In the sign industry around here, 4x4 posts are set 30" deep, minimum, deeper in colder parts of the state (higher altitude). The soil below what is called "frost line" never freezes (never? Well, hardly ever), so if the posts or pilings are standing on that they won't frost heave. The soil above frontline will be cold, and variable depending on insolation and ambient temperatures. The soil 6" down below your snow cave might even be colder than ambient, if the temps have been down for a while. Last edited by Jrrarglblarg; 6th October 2016 at 11:02 AM.
 6th October 2016, 11:32 AM #268 jaydeehess Penultimate Amazing     Join Date: Nov 2006 Location: 40 miles north of the border Posts: 20,843 Originally Posted by Jrrarglblarg Numberless anecdote rejected. The soil maintains a constant temperature of roughly 50 degrees F, but way below the surface. There are laws and building codes for how deep posts and pilings need to be sunk, for that reason. Fence or sign posts that are set too shallow tend to get shoved up out of the soil by the action of freezing water expanding. In the sign industry around here, 4x4 posts are set 30" deep, minimum, deeper in colder parts of the state (higher altitude). The soil below what is called "frost line" never freezes (never? Well, hardly ever), so if the posts or pilings are standing on that they won't frost heave. The soil above frontline will be cold, and variable depending on insolation and ambient temperatures. The soil 6" down below your snow cave might even be colder than ambient, if the temps have been down for a while. Frost heaving and frost line are well known in areas above 49N Yes, and the temp of the soil between that constant temp layer and the surface is a gradient, and between there and the top of the snow is also a gradient that reaches the ambient air temp at the transition between snow and air ( at night or in deep shade). Around here that ambient air can easily reach -30 C and snow cover easily be 3 feet. Our posts, pilings, water lines, sewer lines all need to be 6 feet down and even then we get frozen municipal water supply lines freezing if snow cover is light and temps stay too low too long. Septic fields sport frost fences to keep animals and snowmachines from packing the snow down, destroying insulative properties and freezing the field. Nowadays it would be fairly easy to get temps involved in a snow hut at it's completion and over an unoccupied time period. Can purchase a remote digital thermometer at Canadian Tire for under \$30. Maybe my daughter will give me permission to put my grandkids to work making one in the back yard in February. Unfortunately my health issues would mean it would take me a few days to pile up the snow and hollow it out. (A sure path to possible tragic failure) Interesting but I suspect OT. Back in my teens we would see what it took to destroy them before we left. You could get up on top and jump, hard, on it and even then only a knockout the size of your feet would punch through, often leaving you hanging by the armpits. Last edited by jaydeehess; 6th October 2016 at 11:39 AM.
 6th October 2016, 11:37 AM #269 Jrrarglblarg Guest   Join Date: Nov 2010 Posts: 12,673 Originally Posted by jaydeehess All known. Frost heaving and frost line are well known in areas above 49N Yes, and the temp of the soil between that constant temp layer and the surface is a gradient, and between there and the top of the snow is also a gradient that reaches the ambient air temp at the transition between snow and air ( at night or in deep shade). Around here that ambient air can easily reach -30 C and snow cover easily be 3 feet. Our posts, pilings, water lines, sewer lines al need to be 6 feet down and even then we get frozen municipal water supply lines freezing if snow cover is light and temps stay too low too long. Nowadays it would be fairly easy to get temps involved in a snow hut at it's completion and over an unoccupied time period. Can purchase a remote digital thermometer at Canadian Tire for under \$30. Maybe my daughter will give me permission to put my grandkids to work making one in the back yard in February. Unfortunately my health issues would mean it would take me a few days to pile up the snow and hollow it out. (A sure path to possible tragic failure) Your window of opportunity for this experiment will precede mine. But I'm willing to try it here when we finally get snow. Actually, this year I expect massive snowfall, as I think that's where we are in the cycle-ish weather pattern of dry and wet winters here. I'm in the market for a new remote thermometer gizmo anyway, I guess I'll lurk Home Depot for the multi-sensor package to go on sale. One for ambient, one for the chicken coop and another dedicated to mad science would be ideal. Last edited by Jrrarglblarg; 6th October 2016 at 11:40 AM.
 6th October 2016, 12:06 PM #270 jaydeehess Penultimate Amazing     Join Date: Nov 2006 Location: 40 miles north of the border Posts: 20,843 Originally Posted by Jrrarglblarg Your window of opportunity for this experiment will precede mine. But I'm willing to try it here when we finally get snow. Actually, this year I expect massive snowfall, as I think that's where we are in the cycle-ish weather pattern of dry and wet winters here. I'm in the market for a new remote thermometer gizmo anyway, I guess I'll lurk Home Depot for the multi-sensor package to go on sale. One for ambient, one for the chicken coop and another dedicated to mad science would be ideal. Great. I also contacted a professor at the University of Manitoba, who does a lot of work on cold weather survival. I kept the email to the point not giving hint to which take on this point I fall on. I'll pm you a copy.
 6th October 2016, 12:12 PM #271 Jrrarglblarg Guest   Join Date: Nov 2010 Posts: 12,673 Awesome, I look forward to it. See, despite the efforts of woo merchants, we can find ways to discuss actual science around here. This is much more interesting discussion and useful to the OP topic than wogoga's number system. Because it's about heat flow, heat retention and heat rejection.
 6th October 2016, 12:37 PM #272 Slowvehicle Membership Drive Co-Ordinator, Russell's Antinomy     Join Date: Sep 2012 Location: ...1888 miles from home by the shortest route without tolls... Posts: 17,348 Originally Posted by Jrrarglblarg Awesome, I look forward to it. See, despite the efforts of woo merchants, we can find ways to discuss actual science around here. This is much more interesting discussion and useful to the OP topic than wogoga's number system. Because it's about heat flow, heat retention and heat rejection. I look forward to the responses...and will (if the snow allows) build one of my own for a third data point. __________________ "They want to make their molehills equal to the mountains by cutting the mountains down." -turingtest "The universe did not come from nothing, it came from 'We don't know'." -Dancing David "Cry, booga, booga, booga! and let slip the Hamsters of Silly!" -JFDHintze
 7th October 2016, 09:23 AM #274 jaydeehess Penultimate Amazing     Join Date: Nov 2006 Location: 40 miles north of the border Posts: 20,843 The professor got back to me saying that with no other heat source, interior and exterior temps will be the same after sitting empty. Though it seems no one has tried it. Is a foot of snow enough insulation to create a gradient between interior and exterior? When heat is lost from the earth as frost goes further down, is there enough flow to cause a noticeable gradient? I did find this: http://www.fsavalanche.org/temperature-gradient/ although in avalanche prone areas the snow pack would be very deep. Last edited by jaydeehess; 7th October 2016 at 09:27 AM.
 7th October 2016, 09:48 AM #275 threadworm Graduate Poster     Join Date: Jan 2012 Posts: 1,740 Thread snowdrift. __________________ Facts are simple and facts are straight, facts are lazy and facts are late, facts don't come with points of view, facts don't do what I want them to. ************************** Apollo Hoax Debunked
 7th October 2016, 02:02 PM #276 Jrrarglblarg Guest   Join Date: Nov 2010 Posts: 12,673 The topic flaked out. It's still about heat flow.
 8th October 2016, 12:24 AM #277 steenkh Philosopher     Join Date: Aug 2002 Location: Denmark Posts: 6,334 Perhaps the inside of an igloo feels warmer because there is no wind? __________________ Steen -- Jack of all trades - master of none!
 8th October 2016, 01:13 AM #279 threadworm Graduate Poster     Join Date: Jan 2012 Posts: 1,740 Originally Posted by wogoga The Hindu-Arabic numeral system is apriori simpler and more effective than the Roman numerals. Nevertheless, to the persons having grown up with Roman numerals, the new decimal system seemed more confusing than the accustomed one. Except nobody has grown up with them because they are more complex than Arabic numerals, which is why no-one uses them. [...snip...] Quote: All my examples and calculations of this thread are correct; at least nobody has brought forward evidence that they are wrong. No they aren't, and yes they have. __________________ Facts are simple and facts are straight, facts are lazy and facts are late, facts don't come with points of view, facts don't do what I want them to. ************************** Apollo Hoax Debunked
 8th October 2016, 09:54 AM #280 JayUtah Penultimate Amazing     Join Date: Sep 2011 Location: The great American West Posts: 20,936 Originally Posted by wogoga All my examples and calculations of this thread are correct... No they aren't. But your problem doesn't lie so much in arithmetical error as it does in conceptual incompetence. How you think heat shields work is not how they actually work. You can express your wrong model as arithmetically as you want, but it doesn't make it any more correct. Quote: ...at least nobody has brought forward evidence that they are wrong. Wow. Just, wow.

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