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Jaybro
Social climber
The West
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May 28, 2007 - 04:53pm PT
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"I sort of figured if I posted, Ed might answer" = most direct troll, ever. Toldja. Could have just asked.
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Ed Hartouni
Trad climber
Livermore, CA
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May 28, 2007 - 04:55pm PT
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Should I feel used?
I'll do anything for science!
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Jaybro
Social climber
The West
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May 28, 2007 - 05:05pm PT
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There is no fault on any side, just an observation.
Good weather in Portola/Donner this weekend, BTW.
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TradIsGood
Happy and Healthy climber
the Gunks end of the country
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May 28, 2007 - 05:10pm PT
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hobo, that is only if the shovel handle is parallel to the ground. Otherwise some of that weight is bearing on the point of the shovel.
Likewise the weight lifted is a vector component. Perhaps it would be best for LEB now to reread the wikipedia levers article. Maybe she can make sense of it now.
The normal forces (perpendicular to the lever arm) are the easiest to work with. Of course, one must first do the geometry to calculate what those are.
Now LEB could change the lever class so that she was lifting the shovel. Then she might be able to exert a bit more than her weight on the lever arm (since after all we assume that she can stand on two legs. If she can jump, she can get a bit more than her weight. But it does get complicated here, since forces might be tranferred through the back, arms, and hands.
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rgold
Trad climber
Poughkeepsie, NY
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May 29, 2007 - 12:09am PT
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"I DID google [Wikipedia] levers but I was not able to quite grasp it."
What, LEB, you can't understand nonsense masquerading as scientific exposition? Wikepedia entries in italics, my comments in roman.
The principle of leverage can be derived using Newton's laws of motion, and modern statics.
...but we won't actually do any of that here. Oh, and by the way, the modern statics we use was discovered by Archimedes more than 2000 years ago.
It is important to note that the amount of work done is given by force times distance.
It is also important to note that it will hurt if you drop the lever on your toe. Meanwhile, rest assured that we will never reveal what this has to do with any principle of leverage, and will, for good measure, hide the fact that the real issue is torque.
The lever allows less effort to be expended to move an object a greater distance.
A Houdiniesque compression of falsehoods, half-truths, and mumbo-jumbo into a tiny space. "Effort" is not a term from physics, greater does not have an antecedent, distance is neither defined nor described, when it is this description is misleading at best, and not all lever configurations require less force to balance a given weight.
For instance, to use a lever to lift a certain unit of weight with an effort of half a unit, the distance from the fulcrum of the spot where force is applied must be twice the distance between the weight and the fulcrum.
Change "fulcrum of" to "fulcrum to," get rid of the undefined term "effort," speak more clearly about "balancing" rather than "lifting," make clear that the weight in question is hanging from the lever by something capable of pivoting, explain why all this matters, and this sentence might become almost coherent. Better yet, log on to SuperTopo and ask Ed---oh, I forgot, that's what you did.
For example, to halve the effort of lifting a weight resting 1 metre from the fulcrum, we would need to apply force 2 metres from the other side of the fulcrum.
Halve what "effort?" No previous "effort" has been mentioned.
The amount of work done is always the same and independent of the dimensions of the lever (in an ideal lever).
So LEB lifting a rock and Archimedes lifting the world do the same amount of work. Or LEB lifting a rock 2" does the same amount of work as she would if lifting it 6." Oy vey.
The lever only allows to trade effort for distance.
...it does not, for example, allow to write proper english, and it certainly does not make you should be able to write an explain of science.
I think we better notify Alabama Homeland Security about this.
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Wild Bill
climber
Ca
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May 29, 2007 - 12:35am PT
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"The lever only allows to trade effort for distance.
...it does not, for example, allow to write proper english, and it certainly does not make you should be able to write an explain of science.
I think we better notify Alabama Homeland Security about this."
Haha *snort!*
LEB, let's cut to the chase, shall we? You need to blast them out like these guys here, who are working on the beginning phase of Yosemite Valley construction (1864):
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Wild Bill
climber
Ca
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May 29, 2007 - 12:38am PT
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P.S. from California:
Here we get 'levers' down behind Home Depot, where they hang out in gaggles, dozens of them, and work for $10 an hour.
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jstan
climber
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May 29, 2007 - 01:11am PT
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LEB
As it turns out Newton's laws are expressed very well on the internet. Every action by a Troll has associated with it an equal and opposite reaction by another Troll. Only in this way can Troll(up)/Troll(down) be a classically conserved quantity.
This entire area of study would benefit were all posters treated to a discussion of The Principle of Least Troll. Very powerful methodology.
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Mighty Hiker
Social climber
Vancouver, B.C.
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May 29, 2007 - 01:18am PT
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It should not pass unnoticed that LEB made a funny in her last post. She was talking about deer stealing her crops: "We had enough quantity, however, that we could not eat all the corn so we were OK on that count - if you did not mind the end being nipped off."
This may be a first for LEB on SuperTopo. A pun, too. Hopefully it was intentional, and not a mere spelling error. Perhaps she could become a climber after all. Or a physicist.
It is possible to buy ladybugs at garden supply places. I don't think they're exactly domesticated, but presumably if there's enough aphids and other pests for them to eat, they'll stick around. A discussion of gentlemanbugs can wait for another time.
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jstan
climber
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May 29, 2007 - 01:22am PT
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At this point I would not suggest she choose the latter.
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Off the Couch
Trad climber
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May 29, 2007 - 08:22pm PT
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Sorry to revive this thread, but I laughed when I read LEB's comment that "I read Ed's comments once and immediately gleaned the information I was seeking."
In true LEB fashion, it only took 84 posts!
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jstan
climber
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May 29, 2007 - 08:47pm PT
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Got to be fair though. A lot of those posts were from people like myself who were not especially helpful. Eh?
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Off the Couch
Trad climber
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May 29, 2007 - 08:49pm PT
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Yes, I know Jstan.
But LEB trolls seem like they're longer than most . . . I mean,
Oh never mind.
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jstan
climber
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May 29, 2007 - 08:52pm PT
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No problem.
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jstan
climber
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May 29, 2007 - 10:46pm PT
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A trolling discussion assuredly will go at least 150 more posts. Innocently making OTC’s point for him, as you have, in itself could be a troll. If you were laughing when you made the last post – you were trolling. Very smooth, I must say. My compliments.
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Wild Bill
climber
Ca
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May 29, 2007 - 10:57pm PT
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Which topic has been bandied about? Trolling, or levers?
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Wild Bill
climber
Ca
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May 29, 2007 - 11:10pm PT
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Lois, you are so right.
But like you, I can't keep it all straight. When is it trolling, etc?
Where do YOU think the line is? Is thread drift trolling, for instance? So hard to know?
What about A. Crowley's one-liners? Trolls, or sincere questions?
So many questions . . .
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Off the Couch
Trad climber
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May 29, 2007 - 11:23pm PT
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That's OK jstan. Also, LEB is a hoot.
Sometimes I really do read your posts LEB. But not so much.
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Jaybro
Social climber
The West
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May 29, 2007 - 11:34pm PT
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"We are always suggesting that one or another person here is "trolling" but there is no clear concept of what that is. Many persons who are said to be "trolling" are simply asking a sincere question or else providing some information"
Asking any question, or making any simplistic statement to elicit a response, ala throwing the bait out the back of a slow moving boat, is by any definition a troll.
Some, like the 'OP', are more direct than others.
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