quote:
Originally posted by foaly
quote:
Originally posted by CookieRevised
You simply hang a second chain of the same type as the one you had on both the ends. This does _not_ change anything in the system since the chain would pull equally hard on both sides; aka the two opposite forces (one on the left end, the other on the right end) cancel eachother out. But, it is now a lot easier to see in pic4 why there wouldn't be a movement, not even in a frictionless environment; it's just a closed chain hanging on a irregular object; it is never going to move out of itself.
It would actually, you move the centerpoint of the mass of the chain...
You do not add any more mass to one end than on the other end, therefore eventhough the centerpoint might be vertically lower, it stays in the same horizontal position and thus hasn't any influence on where the chain would move.
What you say is that if you add 10Kg on both ends the chain would suddenly behave differently than before. This is not the case. The chain will not move any differently than before.
Or to put it in another way, what you say is that a lighter chain is going to behave differently than a heavier chain, eventhough the lay on the exact same triangle in the exact same position. yes, the complete system (chain + block) is going to be heavier, but that does not influence the movement of the chain at all.
If you add 10Kg on both the sides of a scale in balance, that scale isn't going to move, it would stay where it is. If you add 10Kg on both sides in an unbalanced system, that unbalanced system isn't going to flip to one side any faster than it was before or all of a sudden flip to the other side. Aka: adding an equal force to both sides of a balance system (which might be in balance or not, doesn't matter) is not going to have ANY influence at all on the balance of that system.
quote:
Originally posted by Chrono
quote:
Originally posted by CookieRevised
It's like saying x/y wouldn't be the same as x+10 / y+10.
1/2 != 11/12 
sorry, I didn't meant "/" as in an divided by symbol. "<=>" or whatever might have been a better symbol; x and y are those formulas provided by Chancer and co above (which I explained in that same post). You can also think of x and y as both ends of a scale and the "/" as the tipping point.
quote:
Originally posted by vaccination
Why ignore half my post? -.-
I didn't ignore anything. In the reply I gave I replied to every bit of your post. See second paragraph (talking about "not possible in real life") and third paragraph (talking about superconductors etc).
quote:
Originally posted by vaccination
quote:
Originally posted by CookieRevised
There is no more (or less) force pulling on the chain on the left side than there is on the right side, ergo, there is nothing to start movement, ergo there is no movement, even in a theoretical frictionless system, no matter what angle or length the two slopes are, as long as both ends are on the same horizontal plane. The system is always in equilibrium.
I'm (almost) sure that if you take those equations from above and work them further out you would see they are equal (you can in theory because there is always a direct relation between the various elements of the two sides (mass, length, angle, etc), by using ratios instead of real numbers)). The more I think about it the more I am convinced of that.
Uhm, yes there is. F = mgh. The force due to gravity is greater on the left side as there is more mass.
No there isn't. You have exactly the same additional force pulling on the right side as you have the same additional mass on the right side! Hence the system does NOT change by adding the bottom chain!
quote:
Originally posted by gif83
I already showed this in both my posts. Maybe it's hard for you to understand that without diagrams. The equations do equate.
Why using 'difficult' equations and 'hard' to understand diagrams when you might solve it with simple logic.
quote:
Originally posted by gif83
I'm still not entirely sure how the "green" chain helps explain how it would slip in neither direction besides just stating that it's obvious.
dunno... because it is obvious* (without the use of equations and too much thinking)?
*A closed chain isn't going to start moving out of itself all of a sudden. reason: see previous posts.
quote:
Originally posted by gif83
It seems to me that the chain underneath does nothing as long as you assume that the top part of the chain doesn't move to start off with. You can't just claim that.
Yes I can claim that. Because if the bottom part isn't going to do anything, as you say, than why should the top part move at all as they are connected... Implying that the top part moves implies automatically that the bottom part would also move, which it does not. And that is the whole essence.
/ 
