Ask any question you want about Physics

originally posted by: Mary Rose
a reply to: Nochzwei

Question: . . . is “free-fall acceleration” the same as or different from “causing itself to collapse”?

Once again I will re-iterate what has already been said. It depends on context, the amount. There is no yes or no answer, the answer is somewhere in between.

'Causing itself to collapse' a badly worded statement to be used in a question because it is not fully related to the subject to be compared, but it is ambiguous contextually. In reality nothing actually free falls, unless in vacuum. There is always resistance.

The amount of resistance posed by a building is however not like passing through a solid object as many people think. As already been described, tall buildings are loaded in a manner that should withstand a delta T range typical for a location. This can be high as 75C, lets say a delta T of 100 for some good safety factor.

Now you have lots of things going on in a material, in a building year on year thermal expansion and contraction, daily loading of the buildings due to wind (not a problem in a small building, but a very large problem for something big. So things move around a bit, expand and contract, and over the lifetime of a building probably show evidence for metal fatigue also.

Without delving into the whole subject once more there is another factor that i have not spoken of which is Yield strength of a material this is the point at which a material will once deformed, undergo plastic transformation rather than elastic, permanently deforming. Kind of a good measure of the breaking point for a material.

The Yield strength of a material decreases as temperature increases, over the normal temperature range, it isn't that bad, and nothing to be worried about if a building is correctly loaded. Bear in mind that engineering standards vary from place to place but often the safety factor can be as low as 5-10x in places. OK so stepping outside the realms of normality, lets say you have a fire which burns long enough and hot enough to reach say, 1000 C, its not hot enough to melt steel, still another 500 C for that (depending on the type of steel) You reduce the Yield strength significantly, and the material is significantly more elastic than before.

The issue with the question posed is that there is no singular event, but a chain of events. You start to break one thing, and then you no longer support what is above it, if it collapses a little bit, that process loads the structure differently and in a way not designed for. There is a lot of potential energy stored in a high rise building. Changing the load bearing, and load rating for any reason can and often does result in collapse. This collapse appears like objects in free fall, but at the accuracy at which you can watch a building fall, i really don't think the resistance supplied by the bottom of a collapsing building do much to really slow things once they get going.

Iv witnessed both controlled demolition and accidental demolition of a building, yes much smaller scale, but both looked very much the same. Give her a hard enough tap in the right place and the potential is there to fall.



Gravity is not that robust? qualify and explain that to me? It seems robust enough to me that I don't think leaving my home from the second floor window is a good idea, regardless of the time of day, week or year.


From what iv read previous and tried to say in this post, the answer has been given, and yes lets take the 911 conspiracy to the correct area.

Thanks for your post way back around page 6 re charge parity violation.

I can't think of any explanation either. It remains an interesting problem.

a reply to: soundstyle

Thank you for plain talk.

Now, what this means is that the government report in question is introducing new physics.

Is that a fair statement?

a reply to: wmd_2008

Kinda odd how after hfgbob was banned, soundstyle signs up shortly afterwards and posts in this thread supporting him and continuing his line of questioning/spamming and in a thread in the 9/11 conspiracy forum, again, supporting him and continuing his line of questioning/spamming.

I smell a sock puppet account!

a reply to: GetHyped

No, just ATS policy showing itself.

On the Board it has been said that in some cases ATS looks the other way after someone is banned comes back under a new username.

Anyway, what difference does it make?

The science is the science and the report is the report, and it's all laid out clearly for people to evaluate.

This is not a matter of taking sides or winning an argument.

It's a matter of science.

a reply to: Mary Rose
1. 9/11 specifics are off-topic here. General physics questions only in this thread.
2. I read the government report NIST NCSTAR 1-9. There is absolutely no new physics in the report. They proved this by using existing physics in a computer model to re-create the failure in the computer model.

There are some engineering lessons about some design limitations of non-rectangular building designs, such that an engineer reading that report probably would not design another trapezoid shaped building the same way as WTC-7, but as someone else said, building performance is a complicated interaction of many things and a non-rectangular building shape and some of the design decisions that were made to accommodate this were a contributing factor.

In other, non-9/11 skyscraper fires used for comparison to WTC-7, the rectangular shape was apparently a contributing factor in lack of collapse, but even in that case the structural engineer advised that building collapse could be imminent because it wasn't designed for that amount of heat and thermal expansion.

I see my question went down few pages ago... I just ask again

Please explain the attraction/repulsion force in this video
(starting at 2:20 till 25:15)

Tesla coil powered light bolt repels human hand and attracts a piece of copper

originally posted by: Arbitrageur
General physics questions only in this thread.

The questions posed to you were general physics questions.

The questions posed to you pertained to:

• potential energy
  
• accelerating mass
  
• kinetic energy
  
• free-fall acceleration
  

originally posted by: Mary Rose
a reply to: Nochzwei

Can you please answer my question:

Introduction:

originally posted by: hgfbob
Simple fact of SCIENCE: if any of the potential energy from the accelerating mass went to destroying itself, it will lose kinetic energy which requires that the building slow in its fall.......but since it did fall at free-fall acceleration, it wasn't causing itself to collapse.

The above is talking about “potential energy,” “accelerating mass,” “kinetic energy,” "slow in its fall," “free-fall acceleration,” and “causing itself to collapse.”

Question: . . . is “free-fall acceleration” the same as or different from “causing itself to collapse”?

Mary g is the accel.
If I understand your ques right. yes they are the same as they are both falling under the effect of gravity.

originally posted by: swanne
What is, in your opinion, the ultimate goal of Physics?

Omniscience?

As Richard Feynman said, his goal was to learn more about nature, which is one of my major goals too. I'm not sure if "physics" has a goal, aside from that, but I'm open to thoughts on the subject.

a reply to: Mary Rose
This question was general physics: www.abovetopsecret.com...

It was answered here, here, and here. I was OK with which was general physics.

I didn't make the comment to you about 9/11 posts until you crossed the line with this post:

originally posted by: Mary Rose
Now, what this means is that the government report in question is introducing new physics.

Is that a fair statement?

That government report is specific to a 9/11 event, and I even responded but don't ask any more 9/11 specific questions here please, ask them in the 9/11 forum.

originally posted by: soundstyle
any mass occurring an interval of acceleration equal to gravity has all resistance below removed in order to allow that mass to accelerate........if there is something there, there is no acceleration.

So, you think soda straws will slow the fall of a 1 ton object?

Maybe in theory, but not measurably. Same thing goes for any structure where the design limits are vastly exceeded.

No, a few bolts shearing off aren't going to slow down the collapse of a massive building to a significant degree, once the collapse is underway, as already explained multiple times. Maybe the fall rate is only 99.99% of freefall, but they are only estimating from a video and are unable to determine the fall rate accurately enough to say if it's actually 99.6% of freefall, or 99.99% of freefall, or some other figure perhaps a hair under freefall rate. If some engineer claims a building is approximately falling at freefall rate, but in actually it's only 99.99% of freefall rate, I'm not going to argue with him, and frankly I don't see how you can assess fall rate to an accuracy of 0.01%, by looking at a video with standard frame rate. Maybe with a high-speed video it might be possible.

originally posted by: Arbitrageur
. . . ask them in the 9/11 forum.

The 9/11 forum is a conspiracies forum, is it not?

a reply to: Arbitrageur

What are you afraid of?

a reply to: Mary Rose

There's a difference between signing up under a new name and signing up pretending to be someone else solely to agree with your previous posts.

"Gee, GetHyped is such an awesome guy, he's totally right in this instance"

originally posted by: Mary Rose
a reply to: soundstyle

Thank you for plain talk.

Now, what this means is that the government report in question is introducing new physics.

Is that a fair statement?

not really, the initial 2005 NIST scientific investigation found no reason why three buildings did what they did.

they stall for three years till a 2008 NIST crew claims, on video, a new physics phenomenon occurred to bring down WTC7 in their own webcast technical briefing from in between the release of the WTC7 rough draft and the final report.

a reply to: ErosA433

Gravity is not that robust? qualify and explain that to me? It seems robust enough to me that I don't think leaving my home from the second floor window is a good idea, regardless of the time of day, week or year.

forget two......how about 8 stories.....go up 8 stories and jump.....that is the distance of constant acceleration seen within a steel framed building....WTC7.

that same rate of acceleration you are experiencing by hopping out your window, we see occur globally and unified within a steel framed building...that same distance of travel.

you are falling through air.
at a specific rate of acceleration, ONLY attainable....by falling through air....

now how is it possible we see this same rate of ACCELERATION reflected in a steel frame.....

hence the initial question to explain this new phenomenon of science, seen only this one time, as the reason given for this occurring.

a reply to: Arbitrageur

So, you think soda straws will slow the fall of a 1 ton object?

I think you were the initial user of 'soda straws'.

Same thing goes for any structure where the design limits are vastly exceeded.

explain please that comment......no falling debris caused enough damage to fall it....little fires are seen, yet we have a 105 vertical feet of global unified acceleration equal to g., and a claim new physics is responsible. They are on video stating this fact....there is nothing you can do to change that fact.
you were asked if you can show how their physics achieves conditions for FFA.
If you can't..fine...no big deal....but the BS you are doing is only losing you credibility amongst peers.

No, a few bolts shearing off aren't going to slow down the collapse

'slow it down'?...you need to start it first.....again, brings us right back to square one.

If some engineer claims a building is approximately falling at freefall rate,

we are not talking about a damaged building collapsing down upon itself in turn causing further collapse of itself

we are talking about lower structural resistance removed to allow upper structural mass to accelerate within a clear path.

a reply to: GetHyped

There's a difference between signing up under a new name and signing up pretending to be someone else solely to agree with your previous posts.

how can one not agree with truth.

point out one item that is misrepresented within the post.

can you answer the question and explain how this new phenomenon of physics occurs where thermal expansion works at low temps to completely remove structural resistance globally within a steel frame building to allow the found 105 vertical feet of unified acceleration equal to g. for 1/3 of it's 6.5 second collapse.

a reply to: Arbitrageur

2. I read the government report NIST NCSTAR 1-9. There is absolutely no new physics in the report.

me too....it was completed by 200 volunteer scientists whom did not find any scientific reason for collapse......since you read it, you know that.

the claim of new physics phenomenon doesn't come for three more years till 2008 nist crew claims this on video from their own technical briefing.

They proved this by using existing physics in a computer model to re-create the failure in the computer model.

proved to whom?????

they refuse to show/release/clarify/validate/peer review the 68,000+ files of data variables that tell the models what to do..how does that prove anything.

no one outside the authors has seen any supporting data proving this new physics phenomenon occurring only on that one day.....and when demanded by the structural community, they refuse.

the rectangular shape was apparently a contributing factor

maybe circular would have been better?.....doesn't matter what shape it is....the continuous load bearing vertical support will be rated to far exceed the expected load.

a reply to: soundstyle

So, the elephant in the room is that NIST, the National Institute of Standards and Technology, which could not be more mainstream, is corrupt.

If it is corrupt, what else in mainstream science and technology is suspect?

originally posted by: soundstyle
a reply to: GetHyped
can you answer the question and explain how this new phenomenon of physics occurs where thermal expansion works at low temps to completely remove structural resistance globally within a steel frame building to allow the found 105 vertical feet of unified acceleration equal to g. for 1/3 of it's 6.5 second collapse.

You seem to be under the illusion that in a large, heavy stressed building, if you cause damage in location X (like from a fire), then that's it. It doesn't happen that way. Take away support in X, and now forces which were not accounted for (including sudden dynamic forces like tons of concrete & steel bashing upon oneself), very quickly travel (at the speed of sound in steel & concrete) across the whole building structure. Now, building components which used to be working under their designed loads are subjected to much higher loads beyond their physical capacity and they blow. No fire nearby necessary. Now, it's even worse. The weight of the building is still all there, and there's even less holding it up. So within a few milliseconds you get supports blowing out all over the building. And you get a chain reaction otherwise known as a collapse. And now almost nothing's holding it up and it falls straight down due to gravity.

Ever play Jenga?

And I think in WTC 7 there was a large diesel fuel tank which caught on fire and so there was a huge fire in the building in many places.