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#81
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Which proves nothing except that you went to a seminar.
Tom K0TAR Richard Clark wrote: On Tue, 13 Apr 2004 21:24:26 GMT, Gary S. Idontwantspam@net wrote: Holding it in your hands is more of an issue if A) you have some sort of wound, and some could contact your bloodstream, or more likely Mercury can be forced through a solid plate of steel. Such is its ability to migrate through barriers. B) if you do not _thoroughly_ clean it off your hands before touching food, rubbing your eyes, smoking a ciggie, etc. Hi Gary, I just attended a Nanotech seminar presentation 4 hours ago on "The Collapse of Langmuir Monolayers" that showed the human body has roughly 2M² of skin surface area, OR 100M² of Lung surface area, OR 300M² of Gastro Intestinal surface area. The later two have a monomolecular air/water interface - the Langmuir layer. The decay products of nuclear breakdown (the electron emission) is no hazard due to its inability to puncture the dermal layer - inside the body it leads to chromosomal breakdowns that gives rise to cancerous growths. Same vector, two different paths separated by lack of caution in the errant belief about exposure levels leads to grief. [Another lesson learned in close proximity to the Boomers, and 24 Nuclear warheads stored within 10 feet of my workbench aboard ship.] 73's Richard Clark, KB7QHC |
#82
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On Wed, 21 Apr 2004 22:12:51 -0500, Tom Ring
wrote: Which proves nothing except that you went to a seminar. Tom K0TAR Hi Tom, Then we can both agree that I speak from a point of knowledge (got the experience too). So, what have you got to offer? ;-) 73's Richard Clark, KB7QHC |
#83
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Cecil,
Could you clarify the dimensions of your column? Because the only portion of a cylinder of Hg that would lengthen is the tiny portion at the tip of the cylinder. Let's say the inner diameter of the tube was 1" (kind of thick for a tube of Hg, but makes for really easy math here... ![]() degree off vertical would only allow the volume residing at the very end to tilt (occupying 1" of cylinder length) and yes, it would (begging the question it had no surface tension) find level again and the bottom edge, effectively lengthening the metallic column by (1.414 * n) where 'n' is the affected volume. (roughly a length of column equal to the diameter of the column) Our 4' column would only lengthen to about 4' plus approx 1/2 an inch. The rest of the column is effectively captive to the inner dimensions (and volume) of the vessel containing it. Bob. Cecil Moore wrote: Jim Kelley wrote: Cecil Moore wrote: By Golly, I have been looking for a cable stretcher. A tilted mercury column will perform that function. How so? The gravity vector remains constant while the tilted mercury vector varies with the angle of the tilt. Let's say theta is the angle of the tilt, i.e. the angle between the mercury column and the ground plane. At an angle of 45 degrees, the mercury column length will be 1.414 times the length at 90 degrees, At 10 degrees, the mercury column length will be 5.76 times the length at 90 degrees. That sounds like something worth patenting. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#84
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Cecil Moore wrote:
David.Shrader wrote: If it's a closed tube then the length does not change with angle. I may be wrong, cuz I'm not very mechanical, but it seems to me that a column of mercury in a tube with a vacuum at the top and a reservoir of mercury at the bottom would change height of column depending on the angle of the column's deviation from vertical. It seems to me that when the column is horizontal, there would be no vacuum at all in the tube. -- 73, Cecil http://www.qsl.net/w5dxp OK. A manometer as opposed to a thermometer. |
#85
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![]() Cecil Moore wrote: Jim Kelley wrote: Cecil Moore wrote: By Golly, I have been looking for a cable stretcher. A tilted mercury column will perform that function. How so? The gravity vector remains constant while the tilted mercury vector varies with the angle of the tilt. Let's say theta is the angle of the tilt, i.e. the angle between the mercury column and the ground plane. At an angle of 45 degrees, the mercury column length will be 1.414 times the length at 90 degrees, At 10 degrees, the mercury column length will be 5.76 times the length at 90 degrees. That sounds like something worth patenting. I saw a further explanation in your later post. Important point - the resevoir, open to air or a source of constant pressure for example. As you tilt the vertical section, the height above ground remains constant because it is balanced by the pressure on the reservoir. In order to maintain the height above ground as the column is being tilted, the column must increase in length. It works beautifully by the way, Cecil. I just tried it with a mercury barometer. 73, Jim AC6XG |
#86
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Well, I gave an answer, farther down the thread, that actually is more
on subject, liquid antennas. I told him where to find a group that knows about them and builds lots of them, which is more than anyone else seems to have done. Looks to me like most of the regulars on this newsgroup, except Roy and a couple others, talk about anything except the subject/question that started the thread. Which is their right. Just don't get annoyed if I point out that fact occasionally. Also the fact that anyone with an IQ above room temperature knows mercury has to be handled with some care. tom K0TAR Richard Clark wrote: On Wed, 21 Apr 2004 22:12:51 -0500, Tom Ring wrote: Hi Tom, Then we can both agree that I speak from a point of knowledge (got the experience too). So, what have you got to offer? ;-) 73's Richard Clark, KB7QHC |
#87
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![]() "Cecil Moore" wrote in message ... David.Shrader wrote: If it's a closed tube then the length does not change with angle. I may be wrong, cuz I'm not very mechanical, but it seems to me that a column of mercury in a tube with a vacuum at the top and a reservoir of mercury at the bottom would change height of column depending on the angle of the column's deviation from vertical. It seems to me that when the column is horizontal, there would be no vacuum at all in the tube. -- 73, Cecil http://www.qsl.net/w5dxp It s good thing you clarified that you were taklking about the "barometer" configuration. Sounds messy to me. -- Steve N, K,9;d, c. i My email has no u's. |
#88
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On Wed, 21 Apr 2004 14:17:14 -0700, Jim Kelley
wrote: Cecil Moore wrote: Jim Kelley wrote: Cecil Moore wrote: Jim Kelley wrote: How much does the length change when you tilt it at 45 degrees? By the factor of the square root of two. Sounds kinda like one of those mythical cable stretchers. :-) By Golly, I have been looking for a cable stretcher. A tilted mercury column will perform that function. How so? Pascal's law. |
#89
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On Thu, 22 Apr 2004 16:10:00 GMT, Dave Shrader
wrote: Cecil Moore wrote: David.Shrader wrote: If it's a closed tube then the length does not change with angle. I may be wrong, cuz I'm not very mechanical, but it seems to me that a column of mercury in a tube with a vacuum at the top and a reservoir of mercury at the bottom would change height of column depending on the angle of the column's deviation from vertical. It seems to me that when the column is horizontal, there would be no vacuum at all in the tube. -- 73, Cecil http://www.qsl.net/w5dxp OK. A manometer as opposed to a thermometer. No, a barometer. 1. Thermometer -- sealed at both ends -- height depends on temperature. 2. Manometer -- open at both ends -- one end open to atmosphere; other end open to space whose pressure you want to measure relative to atmosphere; displacement from balanced level in each column dependent on pressure differential. 3. Barometer -- sealed at top; open at bottom, which is submerged in sizable puddle of mercury; vertical height, from surface of reservoir to top of column (assuming adequately long tube and adequately large mercury reservoir) dependent on pressure, but length of mercury column dependent on tilt of tube. (sec or csc function, IIRC.) |
#90
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On Thu, 22 Apr 2004 18:29:46 -0500, Tom Ring
wrote: Also the fact that anyone with an IQ above room temperature knows mercury has to be handled with some care. So as room temperature drops, more inhabitants of the room become aware of this important caution? |
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