The REAL question when asking, "what is the mechanical advantage?"

Riggs said:
all's you need is Barney the Purple Dinosaur to show up . Thank God I didn't need a chalk board , and a little Mr. Bill to understand climbing . Really , is this where we are ? An instructor , with a cardboard puppet and a chalkboard , and they are both named yo, yo . I don't know about you , but it's time to get a paint brush . I want to recycle little yo yo .
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Uncanny that Poe's law and....Morgan's Maxim just sprang to mind:
"Any sufficiently advanced troll is indistinguishable from a genuine kook."
:D
 
treehumper said:
The only problem I've got with that article is the inconsistency in terms with respect to the levers. We start with applied and resistance forces, then input and output forces, which IMO get mixed up when applied to the effort and resistance arms finally ending up with effort and load arms. As I read it, in Steps 3 & 4 the terms are reversed.

Arggghhhh....... Technical writing 101, define your terms and be consistent. Show the relationship between terms used as a substitute.
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Agreed, not to mention that there is a typo under Third Class Lever when they say lever type - second class. It's actually a Third Class Lever that they are showing and describing, which is correct.
 
Pelorus said:
Uncanny that Poe's law and....Morgan's Maxim just sprang to mind:
"Any sufficiently advanced troll is indistinguishable from a genuine kook."
:D
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I take it that you're just joking by your use of a smiley face, because Riggs is neither a troll nor a kook, he's the real deal as I'm sure you know. Funny how some newer members don't know this though?

Some people just don't care to post about the technical (nerdy) aspect of Mechanical Advantage, but you can be sure that they know as much, if not more than most, about the practical use of it, as Riggs defintely does.

Personally, I like this stuff, though I try not to get overwelmed by it.
 
This thread is about MA, not about children's programs or how information is presented.
If Riggs wants to make fun of the way I present it or even that I should present it or debate the merits of YouTube and such, I wholeheartedly support that he does that.............. in a different thread.
 
chris_girard said:
I take it that you're just joking by your use of a smiley face, because Riggs is neither a troll nor a kook, he's the real deal as I'm sure you know. Funny how some newer members don't know this though?

Some people just don't care to post about the technical (nerdy) aspect of Mechanical Advantage, but you can be sure that they know as much, if not more than most, about the practical use of it, as Riggs defintely does.

Personally, I like this stuff, though I try not to get overwelmed by it.
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I take it that if you are familiar with Poe's Law, then you are quite aware that the smiley face appeared for a reason!
From your long association with the Buzz, I take it that you are also aware that Mr. Riggs is has considerable expertise with presenting himself as a Troll, and perhaps a Kook.
Knowledge can make a person arrogant and condescending. Sad, really.
 
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Getting back to the subject at hand:

Conclusion: (to the article referenced below)
The Take-Home Messages 1. Single sheave pulleys double the input force at their point of attachment (this effect is magnified proportionately, when using multi-sheave pulleys). While this effect can make it easier to move a load, it also can increase the stress on our rigging, with potentially disastrous results. Make sure your anchor systems have sufficient strength to withstand these forces. Always perform a “white-board analysis” prior to putting your raising system to work. 2. Calculate the MA of your pulley system by counting the supporting legs, and including the free end of the rope, if it comes from a Traveling Pulley. 3. To calculate the MA of a piggybacked (compound) system, simply figure the MA of each individual system, and multiply the results. 4. Monitor the stress within your system! Copyright 2006, Ralphie G. Schwartz



http://efclimbers.net/wp-content/uploads/2013/02/pulley-ma-systems.pdf
 
It dawned on me while watching both videos in this thread another way of thinking of why the force on an anchor up in the tree is double the weight of the climber or load. I am pulling on the rope to lift the load with a simple one pulley system. Gravity, our unseen but always present friend, is pulling on the other end of the rope with the same force. I am pulling down with 100 units of force, gravity is also pulling down with 100 units of force, hence the two hundred units that the pulley up in the tree sees.
Maybe this is not the lesson you were trying to teach but you helped me anyway. Thank you.
 
dougfir177 said:
It dawned on me while watching both videos in this thread another way of thinking of why the force on an anchor up in the tree is double the weight of the climber or load. I am pulling on the rope to lift the load with a simple one pulley system. Gravity, our unseen but always present friend, is pulling on the other end of the rope with the same force. I am pulling down with 100 units of force, gravity is also pulling down with 100 units of force, hence the two hundred units that the pulley up in the tree sees.
Maybe this is not the lesson you were trying to teach but you helped me anyway. Thank you.
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By the same token, if you are on a doubled rope system, the friction saver through which the rope moves is like a pulley. So you have a simple one pulley system. If you are on one end of the rope and someone else is pulling you up from the ground, the force they would have to apply is no less than your own weight, so the force at the anchor, the tree limb above is double your weight. However, if you are climbing as usual on that Ddrt system, each leg of the rope is bearing half your weight, so the force at the anchor is equal to your weight.
 
Pelorus said:
I take it that if you are familiar with Poe's Law, then you are quite aware that the smiley face appeared for a reason!
From your long association with the Buzz, I take it that you are also aware that Mr. Riggs is has considerable expertise with presenting himself as a Troll, and perhaps a Kook.
Knowledge can make a person arrogant and condescending. Sad, really.
Click to expand...
that Mr. Riggs is has considerable expertise with presenting himself as a Troll, and perhaps a Kook.

is that right ? awesome . I have to re reads your crap .; get your game up . can't wait too see your response . time to spice up the buzz. don't poke the bear !
 
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