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And hence we have ANOTHER person who cannot tell the difference between
MASS and VOLUME. I feel your frustration. And.. whats sad is.. the person who said 100 pounds probably thought they were being helpful by pointing out something "obvious" Dave RR Urban wrote: Hello All, I am strongly considering the RV-7a and am interested in knowing the dimensions of the baggage area behind the seats. Thanks David "EUTNET" wrote: Baggage 100 lbs +++++++++++++++++ ARRRGH. Go directly to jail. Do NOT pass GO. Do NOT collect $200. Monopoly BOb -- |
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Dave S wrote:
And hence we have ANOTHER person who cannot tell the difference between MASS and VOLUME. I feel your frustration. And.. whats sad is.. the person who said 100 pounds probably thought they were being helpful by pointing out something "obvious" Dave Those that point out the mistakes of others would do well to mind their own. Pounds (lbs.) are a measure of weight, not mass (which in the English system would be slugs). Van's own web page shows the baggage area to be "12+ cu. ft." If you need a more precise number, I would suggest contacting Van's Aircraft directly. http://www.vansaircraft.com/public/rv-7spe.htm Russell Kent |
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On Mon, 08 Dec 2003 09:59:10 -0600, Russell Kent
wrote: Dave S wrote: And hence we have ANOTHER person who cannot tell the difference between MASS and VOLUME. I feel your frustration. And.. whats sad is.. the person who said 100 pounds probably thought they were being helpful by pointing out something "obvious" Dave Those that point out the mistakes of others would do well to mind their own. Heed your own advice, fool. Pounds (lbs.) are a measure of weight, not mass (which in the English system would be slugs). Where'd you get that idea? Gene Nygaard http://ourworld.compuserve.com/homepages/Gene_Nygaard/ Gentlemen of the jury, Chicolini here may look like an idiot, and sound like an idiot, but don't let that fool you: He really is an idiot. Groucho Marx |
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Russell Kent wrote:
Those that point out the mistakes of others would do well to mind their own. Gene Nygaard responded: Heed your own advice, fool. On entirely too many occasions I am indeed a fool, but I don't see where devolving to name calling improves the conversation. Besides gently (IMHO) chastising the intervening poster's rant, I still provided a useful answer to the original poster's question (12+ cu. ft.) and a reference to the source. Russell Kent continued: Pounds (lbs.) are a measure of weight, not mass (which in the English system would be slugs). Gene Nygaard responded: Where'd you get that idea? Uh, 2 years of high school physics (a jillion years ago). Perhaps a few web references will help clear the cobwebs: http://scienceworld.wolfram.com/physics/Slug.html http://www.physics.ucla.edu/k-6connection/Mass,w,d.htm Russell Kent |
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OK, I know it's bad form to follow-up one's own posting. So sue me. :-)
Gene, I see from your signature that this "weight vs. mass" thing is a personal windmill for you. Fine. And I see that slug isn't used anymore (pound-force is the term now). And for non-technical conversations, pound is a unit of mass. Here's a question though: is this forum a technical or non-technical conversation? And look at the sequence of postings: EUTNET wrote that the baggage area dimension was 100 lbs, obviously meaning *weight*, and Dave S. complained that EUTNET "cannot tell the difference between MASS and VOLUME." [emphasis Dave's] So I believe Dave should have instead written "WEIGHT and VOLUME." Now I suspect that Dave S. was merely careless and really does understand the difference between mass and weight, and I was trying to gently pass along the advice that newsgroup corrections are invariably inspected for even the slightest error (see this thread!). I welcome you (Gene) jumping in at that point to correct the whole weight vs. mass, slugs, pound-force hullabalu, but I wish you'd do it with a bit less hostility. Someone may well have ****ed in your cornflakes, but I assure you it wasn't me. :-) Russell Kent Russell Kent wrote: Russell Kent wrote: Those that point out the mistakes of others would do well to mind their own. Gene Nygaard responded: Heed your own advice, fool. On entirely too many occasions I am indeed a fool, but I don't see where devolving to name calling improves the conversation. Besides gently (IMHO) chastising the intervening poster's rant, I still provided a useful answer to the original poster's question (12+ cu. ft.) and a reference to the source. Russell Kent continued: Pounds (lbs.) are a measure of weight, not mass (which in the English system would be slugs). Gene Nygaard responded: Where'd you get that idea? Uh, 2 years of high school physics (a jillion years ago). Perhaps a few web references will help clear the cobwebs: http://scienceworld.wolfram.com/physics/Slug.html http://www.physics.ucla.edu/k-6connection/Mass,w,d.htm Russell Kent |
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On Mon, 08 Dec 2003 15:02:03 -0600, Russell Kent
wrote: Russell Kent wrote: Those that point out the mistakes of others would do well to mind their own. Gene Nygaard responded: Heed your own advice, fool. On entirely too many occasions I am indeed a fool, but I don't see where devolving to name calling improves the conversation. I see that even that wasn't enough to get your attention, Chicolini. How big a bat do I need to hit you over the head with to get your attention? Besides gently (IMHO) chastising the intervening poster's rant, I still provided a useful answer to the original poster's question (12+ cu. ft.) and a reference to the source. Yes, you got that right. Too bad nobody will pat you on the back for it, because you obscured it with irrelevant nonsense, and even worse, an incorrect claim of error on someone else's part. Russell Kent continued: Pounds (lbs.) are a measure of weight, not mass (which in the English system would be slugs). Gene Nygaard responded: Where'd you get that idea? Uh, 2 years of high school physics (a jillion years ago). Perhaps a few web references will help clear the cobwebs: If you found those references, you also found many that got it right. http://scienceworld.wolfram.com/physics/Slug.html Slugs are units of mass. That's not what I'm calling you on. But that little-used 20th century invention, which didn't even appear in physics textbooks before 1940, are by no stretch of the imagination _the_ units of mass in "the English system." Pounds force also exist, but that's also beside the point. Back up your claim that pounds are not units of mass. That's where you falsely claimed that Dave S. was making an error. -- Gene Nygaard http://ourworld.compuserve.com/homepages/Gene_Nygaard/ "It's not the things you don't know what gets you into trouble. "It's the things you do know that just ain't so." Will Rogers |
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Gene Nygaard wrote:
I see that even that wasn't enough to get your attention, Chicolini. OK, you got me there. Haven't a clue who Chicolini is. Should I be insulted? Do you now feel better having insulted me? How big a bat do I need to hit you over the head with to get your attention? Clear, intelligent statements usually work. Besides gently (IMHO) chastising the intervening poster's rant, I still provided a useful answer to the original poster's question (12+ cu. ft.) and a reference to the source. Yes, you got that right. Too bad nobody will pat you on the back for it, (I don't care) because you obscured it with irrelevant nonsense, Irrelevant? Wasn't to me. Nonsense? Um, nope. and even worse, an incorrect claim of error on someone else's part. Perhaps. Uh, 2 years of high school physics (a jillion years ago). Perhaps a few web references will help clear the cobwebs: If you found those references, you also found many that got it right. I just grabbed a few that looked to get to the point quickly. http://scienceworld.wolfram.com/physics/Slug.html Slugs are units of mass. That's not what I'm calling you on. It wasn't clear in your earlier hostile response. But that little-used 20th century invention, which didn't even appear in physics textbooks before 1940, are by no stretch of the imagination _the_ units of mass in "the English system." I'm sorry, you're correct. I didn't mean to imply that they are the only unit of mass. I was taught (perhaps incorrectly) that the unambiguous term for weight (scientific meaning) in the English system was "slugs". Apparently it's also "pounds force" now (it may have been them, too, and I've just forgotten it). Pounds force also exist, but that's also beside the point. sarcasm Whew. Glad we're past that. /sarcasm Back up your claim that pounds are not units of mass. That's where you falsely claimed that Dave S. was making an error. Actually, I intended only to claim that Dave S. incorrectly stated mass when he should have stated weight. From my perspective, the respondent about whom Dave S. was complaining clearly intended "lbs" as a unit of weight. The reference to the slug as the English mass unit was only intended as an offhand remark. Pounds are units of mass in casual (non-technical) conversations, and probably shorthand for "pounds force" in technical conversations. For the record, I don't claim that slugs are the only unit of mass in the English system, and I'm sorry to have inadvertantly made that implication. Russell Kent |
#8
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Russell Kent wrote in :
Back up your claim that pounds are not units of mass. That's where you falsely claimed that Dave S. was making an error. Actually, I intended only to claim that Dave S. incorrectly stated mass when he should have stated weight. From my perspective, the respondent about whom Dave S. was complaining clearly intended "lbs" as a unit of weight. Gene is correct, although mass and weight are equal in the same environment (i.e. good ole earth gravity) so really correcting someone on that is akin to correcting spelling mistakes on use-net.... kind of useless. Lbs IS a measure of mass (to us "common" folk) IFF acceleration is either identified or implied. i.e. My mass is 195lbs at earth sea level. Most people would say then mass = weight and weight = mass. BUT I would say most of us have had experience where that is not true. If you've traveled on an airplane... or ... perhaps flown one grin, the acceleration factor has been at least momentarily increased or decreased... with maneuvering... so even though you weigh 200lbs before the you stepped into the plane, when you banked into that 30 degree turn, you probably weighed something like 250+, but your mass never changed.... When I took physics, mass was measured in a.u.'s & I have no idea what the a stands for, and I think the u just meant "unit" Although I beleive the correction was a bit petty... The hostle response was a bit uncalled for, especially since Gene was correct. Here is a good link that explains: http://www.nyu.edu/pages/mathmol/tex...ightvmass.html ET "A common mistake people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools."---- Douglas Adams |
#9
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Russell Kent wrote in message ...
I'm sorry, you're correct. I didn't mean to imply that they are the only unit of mass. I was taught (perhaps incorrectly) that the unambiguous term for weight (scientific meaning) in the English system was "slugs". Apparently it's also "pounds force" now (it may have been them, too, and I've just forgotten it). I think you mistyped. 'Slugs' are unambiguously a unit of mass. Pounds are ambiguously a unit of force. Ambiguity exists because it is popular in some disciplines to use a unit of mass defined (loosely) as that mass which weighs one pound. But you knew that. -- FF |
#10
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On Mon, 08 Dec 2003 15:43:53 -0600, Russell Kent
wrote: Gene Nygaard wrote: I see that even that wasn't enough to get your attention, Chicolini. OK, you got me there. Haven't a clue who Chicolini is. Should I be insulted? Do you now feel better having insulted me? Doesn't cost you any more to pay attention. It's from the Groucho Marx quote. How big a bat do I need to hit you over the head with to get your attention? Clear, intelligent statements usually work. I know better from long experience. If I hadn't clubbed you over the head, you still wouldn't have looked into it enough to learn the significant amount you have already learned, to be singing a different tune now. Still wrong, of course, but a totally different tune nonetheless. Besides gently (IMHO) chastising the intervening poster's rant, I still provided a useful answer to the original poster's question (12+ cu. ft.) and a reference to the source. Yes, you got that right. Too bad nobody will pat you on the back for it, (I don't care) because you obscured it with irrelevant nonsense, Irrelevant? Wasn't to me. Nonsense? Um, nope. and even worse, an incorrect claim of error on someone else's part. Perhaps. Uh, 2 years of high school physics (a jillion years ago). Perhaps a few web references will help clear the cobwebs: If you found those references, you also found many that got it right. I just grabbed a few that looked to get to the point quickly. http://scienceworld.wolfram.com/physics/Slug.html Slugs are units of mass. That's not what I'm calling you on. It wasn't clear in your earlier hostile response. But that little-used 20th century invention, which didn't even appear in physics textbooks before 1940, are by no stretch of the imagination _the_ units of mass in "the English system." I'm sorry, you're correct. I didn't mean to imply that they are the only unit of mass. I was taught (perhaps incorrectly) that the unambiguous term for weight (scientific meaning) in the English system was "slugs". Must have been an overload of new learning, making you mistakenly express what you thought you knew before. Apparently it's also "pounds force" now (it may have been them, too, and I've just forgotten it). Pounds force also exist, but that's also beside the point. sarcasm Whew. Glad we're past that. /sarcasm Back up your claim that pounds are not units of mass. That's where you falsely claimed that Dave S. was making an error. Actually, I intended only to claim that Dave S. incorrectly stated mass when he should have stated weight. Dave S. said mass. Dave S. meant mass. Dave S. was absolutely correct. Sure, he could also have said weight. But that wouldn't have been clear and unambiguous as what he said was ("mass," of course, is also ambiguous, with several different meanings--but unlike the situation with "weight," only one of the meanings of "mass" is used with a number to express its magnitude). Had he said "weight" instead of "mass," you and many others would likely have misinterpreted it as having something to do with the strength of the local gravitational field. From my perspective, the respondent about whom Dave S. was complaining clearly intended "lbs" as a unit of weight. So what? Weight is an ambiguous word, one with several different meanings. Dave S. made clear which one he meant--and he was right. Yes, those pounds are units of weight. But let's look at the other pounds still in use today. First, consider the troy units of weight. That phrase doesn't set off any alarms with you, I'd bet, nor with anyone else. The troy pounds, of course, aren't used much any more (and were outlawed in Great Britain back in the 19th century). But the troy ounces are still in general use, even enjoying a special exception from the metrication laws of places such as Australia and the United Kingdom. But there is one very interesting thing about those troy units of weight--unlike their avoirdupois cousins, and unlike grams and kilograms, they have never spawned a unit of force of the same name. These units of weight remain always units of mass. There is no troy ounce force and there never has been one. The other pounds still in use today in various places of Europe and Latin America are the redefined metric pounds, which replaced many other old pounds back in the 19th century. They are 500 grams, or half a kilogram, exactly--units of mass. I'm sure that you are aware that not everybody uses pounds to measure this "baggage weight." In fact, most of the people of the world use a different unit. Don't suppose you could figure out what that might be, could you? Tell us what those units are. Here's some help: http://www.google.com/search?hl=en&i...=Google+Search Those kilograms are the proper SI units for this baggage weight. Nobody uses newtons for this weight. Nobody uses poundals for this weight. Nobody uses kilograms force or pounds force for this weight. Nor should they. The reference to the slug as the English mass unit was only intended as an offhand remark. Pounds are units of mass in casual (non-technical) conversations, and probably shorthand for "pounds force" in technical conversations. We don't have separate standards for technical use and for non-technical use. Either way, a pound is 0.45359237 kg. A pound force (also, as you point out, often not distinguished from other pounds) doesn't actually have an official definition, at least in the United States, but it is 4.448 N and change in any of the definitions used. Do I need to go into things like specific impulse, where American engineers often get this quantity in units of "seconds"? There is, of course, also an SI unit called a second--but the SI units of specific impulse are newton seconds per kilogram, or the equivalent meters per second. Those American engineers only got these pseudo-seconds in the first place by being sloppy and calling both a unit of force and a unit of mass by the same name--pound--and then canceling one out with the other. Do I need to go into what it means when NASA tells us that the Apollo 11 Lunar Module had a liftoff weight of 10,776.6 lb? Or hundreds of other similar measurements at various stages of all the Apollo missions? Selected Mission Weights http://history.nasa.gov/SP-4029/Apol...on_Weights.htm Do I need to go into things like British thermal units, and specific heat in Btu/(lb °F)? Do I need to get into poundals? There's another unit, which like the slug is only used in a technical context, only to simplify calculations by making it easier to keep track of the units in the result of those calculations. For the record, I don't claim that slugs are the only unit of mass in the English system, and I'm sorry to have inadvertantly made that implication. Russell Kent Just to make it clear to others who might not pick up on this as quickly as you did, I'll point out that the most common English units of mass are pounds, ounces (avoirdupois or troy), and tons (long or short). Also bushels, as they are used in the commodity markets and grain elevators today--as a specified amount of mass, different for various commodities. Now let's pick up a couple more points from your earlier followup to your own message as well: On Mon, 08 Dec 2003 15:19:03 -0600, Russell Kent wrote: OK, I know it's bad form to follow-up one's own posting. So sue me. :-) Gene, I see from your signature that this "weight vs. mass" thing is a personal windmill for you. Fine. And I see that slug isn't used anymore (pound-force is the term now). Pounds force and slugs are different things. One is a unit of force, the other a unit of mass. Maybe you are getting mixed up with poundals, which are units of force in a completely different different, much older fps system of units. Guess what the units of mass are in that oldest English system of mechanical units. And for non-technical conversations, pound is a unit of mass. Baggage weight is a measurement of mass, in either a technical or nontechnical context. Talking about the sale of cheese in a physics class doesn't change the rules governing its sale. See "Physicist qua Cheesemonger (U. of Winnipeg)" http://groups.google.com/groups?safe...nger&lr=&hl=en Pounds are used both as units of mass and as units of force in technical contexts. Sensible people follow the rules and identify the recent spinoff as "pounds force": American Society for Testing and Materials, Standard for Metric Practice, E 380-79, ASTM 1979: 3.4.1.4 The use of the same name for units of force and mass causes confusion. When the non-SI units are used, a distinction should be made between force and mass, for example, lbf to denote force in gravimetric engineering units and lb for mass. Here's a question though: is this forum a technical or non-technical conversation? That would be one of the least reliable clues to the meaning of any words used here. And look at the sequence of postings: EUTNET wrote that the baggage area dimension was 100 lbs, obviously meaning *weight*, and Dave S. complained that EUTNET "cannot tell the difference between MASS and VOLUME." [emphasis Dave's] So I believe Dave should have instead written "WEIGHT and VOLUME." You believe wrong. Now I suspect that Dave S. was merely careless and really does understand the difference between mass and weight, and I was trying to gently pass along the advice that newsgroup corrections are invariably inspected for even the slightest error (see this thread!). I welcome you (Gene) jumping in at that point to correct the whole weight vs. mass, slugs, pound-force hullabalu, but I wish you'd do it with a bit less hostility. Someone may well have ****ed in your cornflakes, but I assure you it wasn't me. :-) Russell Kent Gene Nygaard http://ourworld.compuserve.com/homepages/Gene_Nygaard/ |
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