hotcommodity

Theres a fine line between the smelting process, and a fire in an office building. Lets not mix apples with oranges. And I'm not a "true beliver," if you were refering to me. I simply point out inconsistencies in the official story, but I have no scruples pointing out inconsistencies in conspiracy theories either.

The map I provided shows where major debris fell. And when I say it would take a long time for fires to cause a collapse, I mean a really really long time, as common sense would tell anyone. People dont pay millions of dollars to build structures that can be brought down by a few fires. With respect to the oklahoma bombing and the wtc bombing, I'm simply showing that it takes more than a few fires to bring down a giant structure such as the wtc's or building 7.

If this is the case, then only one corner of the building would have been heated sufficiently enough to cause a collapse. The weight of the building on top of it would have fallen to the side, which it may have to some degree, and fallen sideways into another building, which didnt happen. It all came down very neatly, and for the most part, in an inward fashion. I can see how this might have happened if the heat was dispersed equally over the entire floor, but it was only heated in one corner. With respect to building 7, lets look at a map of where it was in relation to the wtc towers: http://www.wirednewyork.com/wtc/wtc_map.htm You can see that the building is nowhere near the wtc towers, or the heavy debris from the crashes. Even if the explosions caused a few fires in building 7, which, I have no clue how they possibly could being so far away, then that wouldnt have brought building down. By insanes and your admition, it takes alot of burning, at high temperatures, and alot of impact, to bring down a building. And lets say for the sake of argument that fires could indeed cause the collapse of a steel structured building. If that was the case, and there were a few fires in building 7, common sense would tell you that it would take a long time for the fires to consume so much material that it may cause the collapse of the building. You cant use one set of logic for the collapse of one building and a totally different set of logic for the collapse of another. Recall the first attack on the wtc when bombs were set off near the pillars holding up the structure. Not even bomb explosions could cause the collapse of those towers. You may also recall the oklahoma bombings, where the bomb took out a big part of the building yet there was no collapse. It takes alot of power to bring down such a giant structure, yet you believe a few fires can do the trick. This is completely illogical.

Lets say the metal was at a point of malleability, it would need to be beaten to bend, yet nothing was there to apply that force after the explosion. But I will take your points into consideration and study this further. I'm not one to think I know it all. I always like to say that if you can sway my opinion by way of fact or logic, then so be it. I suppose the steel melting issue is up in the air for now. I'll edit this post and get something intelligible put together sometime soon concerning other matters, as I'd like to hear everyones take on them.

There are only three physical states; solids, liquids, and gases. If it was initially a solid, as the steel beams were, the next state would be one where it is melted. It doesnt matter how hot the substance gets, it will still be a solid until its melting point is reached. All materials have a certain heat capacity, and the increasing heat of the burning fuel would naturally be taken on by the steels heat capacity. It would definitely heat the steel, but not weaken it. Everytime I've seen a building fall on its own, it has fallen sideways, thats simply because the bottom part of a buildings structure tends to hold. When was the last time you've seen a building fall all by itself and inward? And I'm sure you've seen controlled demolitions, and what happens there? The building always falls inward so as not to damage other buildings. This is where we need to use logic rather than extreme rationalization. Larry Silverstein said "pull it," then they break to a video of the collapse of the building...come on. If he meant pull the firefighters out, then he would have said just that, but its necessary to follow the context that its in. He says "pull it," and they show the building collapse.

I understand where you're coming from, but again, the collapse was a result of a controlled demolition. Buildings do not have the tendency to collapse inwards, unless each successive floor is blown out, implicative of a controlled demolition. I know you like people to back up what they say with evidence, as do I, so I'll do just that. Larry Silverstein appeared in a PBS documentary called Rebuilding America where he says that building 7 was "pulled," in other words, a controlled demolition: http://video.google.com/videoplay?docid=-7750532340306101329&q=larry+silverstein So the question stands, how could they pull the building within a matter of hours when controlled demoltions takes months to set up? Additionally, you mentioned that the impact and burning of jet fuel caused the collapse of the twin towers. However, the towers were made of steel beams. Steel melts at a temperature of roughly 2500°F, but jet fuel burns at a temperature of 1796 °F. You could pour burning jet fuel on steel all day and iits not going to do a thing to it, because it can only burn at a rough maximum of 1796 °F. This is only part of whats wrong with the official 9/11 story, but I'll see how you respond to this, then we can proceed.

You're exactly right, when people dont do their homework they can end up looking like fools. But this does not dismiss the fact that there are indeed issues to be dealt with concerning 9/11. I'll take it a step further with respect to the Silverstein issue. Building 7 came down due to a controlled demolition. The building did not need to be demolished as it had little to no damage. Additionally, it takes months to set up a controlled demolition, and yet they were able to demolish the building in a matter of hours. There is something seriously wrong with this picture.

Its true that some of the theories surrounding 9/11 are completely stupid. But why not tackle the issues that have validity? For instance, why was building 7 destroyed when it had little to no damage whatsoever? I suppose it was just a coincidence that Larry Silverstein, the owner of the trade center complex, took out a multi-million dollar insurance policy and bought up building 7 just a few months before the event.

Alright I get it, thank you both

EPE is just the electric potential energy. But I think I get what you're saying, the difference is a point charge creates and electric field, and a test charge, with negligible charge is placed into an electric field to measure the electric force that acts on the test charge itself, right?

What is the difference between a point charge [math] q [/math] and a test charge [math] q_0 [/math] ? When dealing with electric potential, my book gives one equation when dealing with a test charge: [math] V = EPE/q_0 [/math] and one when dealing with a point charge: [math] V = kq/r [/math] Why is there a difference between the two?

Haha, ok, point taken.

I appreciate your advice, I had a feeling it was probably sleep and/or stress related. Whenever I take an asprin it seems to releave it quite quickly. I'm in pretty good shape otherwise, I run when I can and eat pretty decent. I'll take your advice and relax more, I'm on spring break now so its good timing, thanks again. With respect to going to the doctor as the other posters mentioned, I cant, I dont have health insurance beyond my school doctor, who would probably tell me to see another doctor anyways. Oh and one more question: Is there anything specific I can eat or exercise that I can do to improve whatever nerve damage I may have caused? Thanks...

I dont see any problem... Edit: When I worked the problem, I got 1.026 g/ml. I simply canceled out terms to find the density... (1.00 mol KCl/ 1L) * ( 1 kg / 0.9750 mol KCl) * (1000 g/ 1 kg) * ( 1L / 1000 ml) = 1.026 g/ml Are you sure there wasn't more to the problem?

So I've been having a problem for about 4 months now with my head. I'm asking about it here because I'm not sure what the problem is, and I would appreciate some educated opinions on the matter. It began with a tender feeling in the upper-left-backhand corner of my head, the sort of feeling being it felt a bit bruised to the touch. I had pulled muscles in my shoulder blade (nothing all that serious) 4 years earlier and had been popping my back since, as it would get stiff from time to time. I took the tenderness in my head as being a result of me popping my back and somehow effecting the muscles in my head. Well that tenderness stopped for the most part a few months ago. I'm not sure if it was directly after it stopped or a few weeks after that when the front-top-left corner of my head bean to have the same tenderness feeling. Up to this past week it had been tender in that spot. Sometimes when I would turn my head I would get a sharp shooting pain that would last 2 seconds or so and it wasnt a tender feeling, it hurt. I've had these shooting pains about twice a week in the past month. Also in the past week I started sleeping flipped around on my bed placing my feet where my head used to be and my head where my feet used to be. The first night I did that things improved noticlably. Well today I'm now feeling the tenderness in the right-top-front corner of my head, and the other parts of my head are not tender. Its beginning to worry me. I thought this may be a result of little rest and a bit of stress from my classes. Monday through Friday I probably get about 5 hours of sleep a nigth on average. I've been known to be overly worrisome but I dont know what to do now. I cant go to a doctor at this stage in my life as my dads out of work and being a college student I dont have money myself. I've looked at symtoms for brain tumors and cancer but I dont believe I fit any of them, my memory is fine and I'm not passing out or anything. Is this something serious, or could it simply be corrected by more sleep/better diet/etc. ?

I'll probably get warned for this but dude, you're an asshole. Confine your posts to physicforums where people take your crap and stay away from here

lmfao Edit: sorry, but i lol'd

Seeing as you just joined this month you seem a bit quick to judge. It may serve you best to stick around and bring something to the table. This place may not be the most active but regulars like Atheist, Cap'n, woelen, dave, swansont, and others make it a great place to be apart of. If you post here regularly as well, you just may find that this place has alot of experienced posters that will gladly enlighten you, thus making it a worthwhile stay

It does help, and I appreciate you taking the time to answer. I finally get that if you have 2 vectors in [math]\mathbb{R}^3[/math] that they are in [math]\mathbb{R}^3[/math] but do not span [math]\mathbb{R}^3[/math]. That was one of things I was confused about, and it makes sense now that if you only have 2 vectors the most they can span is [math]\mathbb{R}^2[/math]. I'm not sure what you mean by "bijection" however. Beyond that I think I have a decent grasp on the rest, and again I appreciate your help

I need to know if I understand subspaces correctly so if anyone can point out any flaws in my thinking it would be well appreciated... If you have 2 vectors, each with 3 real numbers, the vectors exist in [math]R^3[/math]. Since there can only be 2 pivots at the most, the subspace that the vectors generate is in [math]R^2[/math], but not any higher. A question here: Is there any way that the subspace could exist in [math]R^3[/math]? If you have a set of vectors and you're looking to generate a basis for a subspace, the vectors must be linearly independent, that is, having the trivial solution [math] 0 [/math] as its only solution when the vectors are augmented into A[math]x[/math]=[math]0[/math] form. Additionally, the vectors must span [math]R^m[/math] for an mXn matrix ( if the vectors were linearly dependent, they would not span [math]R^m[/math]). Given these conditions we can generate the basis for a nullspace and/or column space. The vectors that form a basis for the column space of A are simply the columns in the original matrix A that have a pivot in their columns when row reduced. The vectors that form a basis for the nullspace of A is the solution to the homogeneous equation A[math]x[/math]=[math]0[/math]. A question here: If the conditions for the basis of a nullspace are the vector solutions given in parametric form, then how can the original vectors augmented to form the matrix A have been linearly independent? When I get the solution, it looks as tho' my text ignores the parameters in the solution and gives the vectors as the basis for a nullspace. Finally, if we want to find a vector in the column space we can simply choose any column of A as a vector and it will be in the span generated by the columns of A. If we want to find a vector in the nullspace then we solve for the equation A[math]x[/math]=[math]0[/math] and choose any real number for the parameter. Last question: Can the zero vector count as a subspace or a nullspace?

In case you're still interested in how it works... [math] \int_{-4}^{0} \sqrt{16 - x^2} \,dx [/math] We let [math] x= 4sin(\theta) [/math], therefore [math] dx= 4cos(\theta) d\theta [/math] Now when we plug in these values we get [math] \int_{a}^{b} \sqrt{16-16sin(\theta)^2 }*4cos(\theta) d\theta [/math]. I put a and b for the endpoints because they will change twice throughout the entire problem and we can plug in the values when we get to the end. Remembering our trig identities we now have [math] 16 \int_{a}^{b} \sqrt{1- sin(\theta)^2}* cos(\theta) d\theta = \int_{a}^{b} (cos(\theta))^2 d\theta [/math] Next we use a half-angle formula to get [math] 8 \int_{a}^{b} 1+ cos(2\theta) d\theta [/math]. Now we can use [math] u-substitution [/math] letting [math] u= 2\theta [/math] and [math] du= 2 d\theta [/math] . Finally we get [math] 4 \int_{a}^{b} 1+ cos(u) du = 4 [u+ sin(u)]^b_a= [ 2\theta+ sin(2\theta)]^b_a [/math]. We know [math] \theta= arcsin(x/4) [/math] so we plug in each original endpoint for x to get the new endpoints, and evaluate the function using the fundamental theorem of calculus. I got 12.6 for my answer.

I suppose its not too uncommon. The first calculus based physics book I got had a wrong solution for about every 10 problems. I got it from my Physics department when they were giving away books, I guess you get what you pay for =/

You want to treat part 3d. as if there were absolute value bars outside of both sums being multiplied. So you would have | (x-1)*(x+2) | = 3. Now you can just multiply the two terms and get |x^2 +2x -x -2 |=3, now just add like-terms and solve. For part 4, one way to sketch a graph would be to simply plot points on an x-y graph. Start by picking whole numbers of x, both negative and positive and close to 0, 0 included. Remember if you get a negative value in the absolute value bars to simply make it positive. The line you graph should never go below the x-axis. I hope that helps.

I thought it was over r squared instead of d squared...or are they the same thing?

Ugh, he's hugging 5 of'em at one time, and crawling on his hands and knees all over their cage. Who knows what type of hybrid disease he's carrying around