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Carpal Tunnel
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Dear Keiva: I challenge you to find another "retronomic" scientific unit. I doubt that there are any.
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old hand
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Sorry to be so late, WW - I forgot where this thread was. (Senility, you know) Anyhow, TEd explained the heat pumping cycle of a refrigerator quite well, but nobody's mentioned that in earlier times electricity was thought to "condense" on a plate in a capacitor, leading to the misnomer, electric condenser. As for running the car's A/C with the windows open, I don't think I've ever seen a compressor ruined by doing so, but it would be possible. Some recent A/C systems run the compressor constantly, and control the temprature through the use of a suction throttling valve, while others use a fixed orifice. The older systems with both a compressor clutch and an expansion valve seemed a bit more prone to failure. I've been out of automobile service for ten years, so I'm not really up to date on this stuff anymore. Now, if you want to know about chain saws or lawnmowers...  This brings up yet another question: Why do we refer to the refrigeration system of an automobile as "air conditioning?" A heater also "conditions" the air, as do the emissions of a passenger who hasn't showered in some time, etc.
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Carpal Tunnel
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Carpal Tunnel
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In reply to:
I remember reading somewhere that he had dissected some frogs legs, and hung the muscles in a way that they came in contact with metal, and twitched.
And reading accounts of his experiments was one of Mary Shelley's inspirations for Frankenstein.
Bingley
Bingley
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Carpal Tunnel
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Bill:
There is heat input, but nowhere near enough to burn you. Yes the gas heats up, but for exactly the reason I stated. More molecules in a smaller volume.
Ted
TEd
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addict
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addict
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I remember reading somewhere that he [Volta] had dissected some frogs legs, and hung the muscles in a way that they came in contact with metal, and twitched.
I always thought that was a Mr. (or M.) Galvan, namesake of words like "galvanize" who did the twitchy frog experiments, but I can't find anything online about it. Anyone else know more?
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Carpal Tunnel
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Dear Flatlander: I goofed. You are correct. Another of my senile moments.
Dear TEd: I kid you not. If you press a fingertip over air outlet of a bicycle pump firmly, depress the plunger forcefully, and then let up finger over air outlet just enough to let a small amount escape under pressure, and you can indeed get a burn and blister, though you may have to depress plunger several times. I have experienced this. Remember the mechanical equivalent of heat. Count Rumford discovered that if a drill for boring cannons got dull, so that no more metal was removed, heat continued to be produced as long asd you kept turning the drill, because the work was being converted to heat.He could keep water boiling away as long as the drill was turning while forced against the metal of the cannon being made.
The same effect takes place in an refrigerator compressor. But when you cool the compressed gas to environment temperature, and then let it expand in the food compartment, it can take up heat. But in a hot environment, the compressor has to work harder. I think this is what the engineer told Wordwomd.
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old hand
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old hand
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Interesting that essentially all terms for electrical units are eponymousIt has been my experience that almost all of the SI units are eponymous. The only ones that aren't seem to be metre, kilogram, candela, mole, and second. See http://physics.nist.gov/cuu/Units/units.html
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Carpal Tunnel
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OP
Carpal Tunnel
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Dear Bean: I had a patient named Candela, and she was not very bright. But not eponymic material.
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old hand
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old hand
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always thought that was a Mr. (or M.) Galvan
Luigi Galvani. His wife divorced him, charging that electricity had become his mistress, and he had become revolting, without a scintilla of affection, since he was given to rubbing his rod in cat fur in a futile attempt to build a perpetual motion monorail - OOps - I'm stepping on someone else's lines!
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