|
Welcome to the International Skeptics Forum, where we discuss skepticism, critical thinking, the paranormal and science in a friendly but lively way. You are currently viewing the forum as a guest, which means you are missing out on discussing matters that are of interest to you. Please consider registering so you can gain full use of the forum features and interact with other Members. Registration is simple, fast and free! Click here to register today. |
2nd July 2011, 09:18 AM | #1 |
Muse
Join Date: Apr 2008
Posts: 686
|
Lamp posts and the pentagon
I've a mate who flies the 9/11 conspiracy flag. He claims this math proves to him that there is something wrong with the official story
"once again i must insist you show your sums - F=MA in relation to lamposts at pentagon (I could use any no of anomalous events contradicting the laws of physics) F = 80000kg (mass of 767) x 154 ms (official speed of planes) so F = 12320000 N or 2,769,646.178992 lbs So a force of over 2 million pounds occurs 5 times to parts of a flimsy Aluminium air frame and it flies on - no damage. Im sure you ll want to correct me if i have made an error." He claims there are plenty of things that happened on 9/11 that goes against the laws of physics. He won't come here to debate so i'm wondering what seasoned debunkers think of this. |
2nd July 2011, 09:21 AM | #2 |
Master Poster
Join Date: May 2006
Posts: 2,152
|
I have always found this "no damage" claim amusing. How exactly do they know that the plane was not damaged? It was blown into a million pieces less than a second later. Did anyone have time to inspect the wings for damage in the meantime?
|
__________________
I said lots of things in NPH that I would not say today and that I did not repeat in NPHR, where I specifically corrected at least some of the errors I had made in that earlier book, written 5 years ago. -David Ray Griffin- |
|
2nd July 2011, 09:24 AM | #3 |
Muse
Join Date: Apr 2008
Posts: 686
|
|
2nd July 2011, 09:26 AM | #4 |
Skeptic not Atheist
Join Date: May 2007
Location: West of Northshore MA
Posts: 24,748
|
|
__________________
"Remember that the goal of conspiracy rhetoric is to bog down the discussion, not to make progress toward a solution" Jay Windley "How many leaves on the seventh branch of the fourth tree?" is meaningless when you are in the wrong forest: ozeco41 |
|
2nd July 2011, 09:27 AM | #5 |
Guest
Join Date: Sep 2006
Posts: 17,252
|
|
2nd July 2011, 09:33 AM | #6 |
Philosopher
Join Date: Oct 2009
Posts: 5,759
|
If you quoted him correctly, he's clueless.
Let's blame the "154 ms" on you, and assume he meant 154 m/s. He's still clueless. Multiplying mass (kg) times velocity (m/s) yields momentum, not force. Momentum is conserved. The large momentum (not force) means the plane would have continued forward regardless of any damage it may have sustained. When a guy can't even get his units right, and doesn't understand the implications of the large number he calculated, then he's just clueless. |
2nd July 2011, 09:41 AM | #7 |
Philosopher
Join Date: Oct 2009
Posts: 5,759
|
There's a dead giveaway. His calculation was completely independent of the strength of the lamp poles. He'd have gotten exactly the same numbers had he been talking about 5 toothpicks instead of 5 lamp poles.
A 767 that's flying at hundreds of kilometers per hour isn't going to be damaged or slowed very much by 5 toothpicks. Hitting 5 lamp poles would have caused some damage and slowed it down slightly, but not enough to matter. |
2nd July 2011, 09:54 AM | #8 |
Master Poster
Join Date: May 2006
Posts: 2,152
|
Ask your friend to stand in front of an oncoming train. Based on his logic the train should suffer massive damage and thrown completely off of the tracks.
|
__________________
I said lots of things in NPH that I would not say today and that I did not repeat in NPHR, where I specifically corrected at least some of the errors I had made in that earlier book, written 5 years ago. -David Ray Griffin- |
|
2nd July 2011, 09:56 AM | #9 |
Skeptic not Atheist
Join Date: May 2007
Location: West of Northshore MA
Posts: 24,748
|
|
__________________
"Remember that the goal of conspiracy rhetoric is to bog down the discussion, not to make progress toward a solution" Jay Windley "How many leaves on the seventh branch of the fourth tree?" is meaningless when you are in the wrong forest: ozeco41 |
|
2nd July 2011, 09:56 AM | #10 |
Graduate Poster
Join Date: May 2006
Posts: 1,077
|
Lamp post are designed with break-a-way bases so that if hit the pole will beak off and
fall away Helps prevent fatal injury if the pole would suddenly stop the vehicle like a telephone pole or tree An airliner weighing some 250,000 lbs at ~ 500 mph is not going to be bother much by couple of lamppost - especially if designed to break off when struck by car |
2nd July 2011, 10:00 AM | #11 |
Skeptic not Atheist
Join Date: May 2007
Location: West of Northshore MA
Posts: 24,748
|
|
__________________
"Remember that the goal of conspiracy rhetoric is to bog down the discussion, not to make progress toward a solution" Jay Windley "How many leaves on the seventh branch of the fourth tree?" is meaningless when you are in the wrong forest: ozeco41 |
|
2nd July 2011, 10:02 AM | #12 |
Muse
Join Date: Apr 2008
Posts: 686
|
|
2nd July 2011, 10:05 AM | #13 |
Muse
Join Date: Apr 2008
Posts: 686
|
here's a link to the youtube debate, i'm not the fkn newz but my mate is
http://www.youtube.com/all_comments?v=l0jbDeSavyU |
2nd July 2011, 10:48 AM | #14 |
Penultimate Amazing
Join Date: Jul 2007
Posts: 18,863
|
Hello? It gets even sillier. They are designed to fall over easily when hit by a car at the bottom.
How much more energy can an aircraft deliver to the bottom of the poles by hitting them at the top, compared to the energy the aircraft absorbs. I somehow don't think the pole is going to win. |
__________________
No civilization ever collapsed because the poor had too much to eat. |
|
2nd July 2011, 11:57 AM | #15 |
Graduate Poster
Join Date: Apr 2009
Posts: 1,883
|
|
__________________
I'll go with the qualified experts, over some ranting guy on the internet that claims he has "the truth". Always beware of those that overuse, capitalize and blanket themselves in them word "truth". I may not always know the truth, but i do know when i'm being lied too. |
|
2nd July 2011, 12:17 PM | #16 |
Master Poster
Join Date: May 2009
Posts: 2,847
|
deleted
|
__________________
DoYouEverWonder - Engineers and architects don't have to design steel buildings not to collapse from gravity. They already conquered gravity when they built it. - Professional Wastrel |
|
2nd July 2011, 02:22 PM | #17 |
Penultimate Amazing
Join Date: Oct 2006
Location: Dog House
Posts: 26,122
|
Lamp post would not stop anything, they have been engineered to fall down when cars hit them so people will not die. They would not stop a 757/767 in the last few seconds of flight the plane will not stop or blow up due to lamps. Breakaway lamposts. Did you tell him the story of a navy jet which cut a thick ski lift cable and flew back and landed. http://www.nytimes.com/1998/02/04/wo...ift-cable.html |
2nd July 2011, 02:24 PM | #18 |
Muse
Join Date: Apr 2008
Posts: 686
|
here's his response
Are the following facts wrong - mass of a 767 is 80000 kg - Airspeed of the pentagon 767 was 555 km ph The Light poles weigh 150 kg ? and of course F=MA . You say you doubt i am presenting a solid scientific case. Is that because my sums are wrong or you want the last word? I use humour but not here because I want a rational debate about impact damage. perhaps your not capable? or you are just a poor loser. still waiting for you to dispute any of my figures, ready when u are |
2nd July 2011, 02:34 PM | #19 |
Muse
Join Date: Apr 2008
Posts: 686
|
he's responded by saying this
Velocity hahahah oh dear - Im sure i have written F=MA many times - enough to establish what formula were dealing with. A stands for ACCELERATION not speed. which is correctly written m/s squared but youtube doesnt allow that little 2 -So you have a small point - Now that were on the same page ..are we? F does = MA and ill help you complete any calculation of a mass of 80000 kg using it - shall we proceed ? or would you like to squirm a bit about that velocity thing |
2nd July 2011, 02:47 PM | #20 |
Master Poster
Join Date: Dec 2008
Posts: 2,278
|
You know, if he used the ^ I'm sure youtube would allow it, hence m/(s^2) would suffice. I find it incredible that all these 'experts' on the internet would even be so bold as to debate an MIT mathematics PhD on units. What I would suggest is that you refer the poster to a high school physics textbook and brush up on Newtons laws, paying particular attention to the concept of impulse.
|
__________________
"Is your claim that the level of penetration is only governed by distance and not the material that is being penetrated?" - DGM |
|
2nd July 2011, 02:47 PM | #21 |
a carbon based life-form
Join Date: Nov 2005
Posts: 39,049
|
|
2nd July 2011, 03:27 PM | #22 |
Scholar
Join Date: Sep 2009
Posts: 51
|
What youtube allows is not the point. Your mate calculated mass x speed and stated that this was a measure of force. The exact quote is "F= 80000kg (mass of 767) x 154 ms (official speed of planes) so F = 12320000 N or 2,769,646.178992 lbs." That's a bad error. He won't own up to it. What does that tell you?
|
2nd July 2011, 03:38 PM | #23 |
Misanthrope of the Mountains
Join Date: Mar 2007
Posts: 24,133
|
Beyond all that I'm sure the posts did damage the plane. How much we'll never know.
Does he have any evidence that the plane was not damaged? I mean until he has some evidence for the plane not being damaged all this talk about calculations is putting the cart ahead of the horse. |
__________________
"Because WE ARE IGNORANT OF 911 FACTS, WE DEMAND PROOF" -- Douglas Herman on Rense.com
|
|
2nd July 2011, 03:46 PM | #24 |
Philosopher
Join Date: Oct 2009
Posts: 5,759
|
He's clueless. By saying "The Light poles weigh 150 kg", he may be hoping you'll assume his "154 ms" (which you quoted correctly, and I apologize for even raising the possibility that you had not) really meant "154 kg", but mass (kg) times mass (kg) is even farther from force than mass times velocity.
He's clueless. He could have written 154 m/s/s instead of 154 m/s, but the facts show no acceleration of 154 m/s/s, which is an acceleration of 15.7 times the acceleration of gravity. No, his 154 m/s is more likely to have been something of an underestimate of the 757's velocity during its last few seconds. It makes far more sense as velocity than as acceleration. As BCR notes, what we have here is an anonymous YouTube poster getting into an indirect argument with a PhD in the relevant subject and then trying to save face by lying about what he had posted. As BCR notes, the concept of impulse is indeed relevant, and you want to compare the plane's momentum (approximately 12320000 kg∙m/s, although that figure is a tad low because your mate underestimated both the loaded mass of the 757 and its velocity) with the momentum lost by hitting a 150 kg lamp pole (approximately 150 kg times the velocity of the aircraft, which would be about 23100 kg∙m/s using your mate's underestimate of velocity, resulting in a delta-V whose consequences can be estimated by dividing 23100 by 12320000: less than 0.2%). ETA: Because the plane hit the light poles near their tops rather than dead center, each impulse would have been substantially less than estimated in the previous paragraph. |
2nd July 2011, 03:53 PM | #25 |
Philosopher
Join Date: Nov 2010
Posts: 7,296
|
I really don't know where to start, but let's play along with the arbitrary use of F=MA as previously depicted, where A appears to equal V... and stay simplistic and accept some of the OP data.
ETA - oh, overtaken by Clinger: what he said. I blame the interweb disconnecting.... ;-) |
__________________
What do Narwhals, Magnets and Apollo 13 have in common? Think about it.... |
|
2nd July 2011, 04:00 PM | #26 |
NWO Kitty Wrangler
Join Date: May 2006
Posts: 29,690
|
Anyone who "insist[s] you show your sums", but can't distinguish between velocity and acceleration isn't worth the effort to correct, and probably isn't even capable of understanding the correction, in any case. Analysis of a collision is far more complicated than just "F=MA", and he can't even get that part correct.
|
__________________
Obviously, that means cats are indeed evil and that ownership or display of a feline is an overt declaration of one's affiliation with dark forces. - Cl1mh4224rd |
|
2nd July 2011, 04:05 PM | #27 |
Muse
Join Date: Apr 2008
Posts: 686
|
here is the latest response
you are confused by the acceleration /velocity conundrum - go read /google a bit and come back for humble pie - when a moving mass hits a stationary one the speed(of moving mass) is the acceleration for th purpose of F=MA - nice to have you aboard but sharpen up - next |
2nd July 2011, 04:17 PM | #28 |
NWO Kitty Wrangler
Join Date: May 2006
Posts: 29,690
|
Absolute bollocks. The only way this could be true is if, in every singly case, the velocity of the moving mass dropped to zero over exactly one unit of whatever unit of time you're using. Acceleration is a change in velocity over time, so it never makes sense to use velocity in its place. Unless he can determine what the change in velocity was when the plane hit the post (which would involve the momentum and impulse calculations mentioned earlier, btw, in case he wants to entertain us with some more of his "math" and "physics"), his F=MA delusions are just that - delusions. BTW, any links to us? This last bit would make a great Stundie contender! |
__________________
Obviously, that means cats are indeed evil and that ownership or display of a feline is an overt declaration of one's affiliation with dark forces. - Cl1mh4224rd |
|
2nd July 2011, 04:21 PM | #29 |
NWO Kitty Wrangler
Join Date: May 2006
Posts: 29,690
|
Edit by post: What he has calculated, with his "80000*154" numbers is the force needed to slow the plane from 154 m/s to 0 m/s over the space of 1 second. That's what an acceleration of 154 m/s/s means. Since gravity is about 10 m/s/s, that means he's using about 15.4G worth of acceleration, which is nonsensical.
ETA: re: "go read /google"; why doesn't he do that, and provide links, if he's so smart? I'll eat all the humble pie he wants me to if he can find any legitimate* reference to support his fantasies. *Textbooks would be nice, not that I imagine he's all that familiar with such things. |
__________________
Obviously, that means cats are indeed evil and that ownership or display of a feline is an overt declaration of one's affiliation with dark forces. - Cl1mh4224rd |
|
2nd July 2011, 04:37 PM | #30 |
Muse
Join Date: Apr 2008
Posts: 686
|
|
2nd July 2011, 04:43 PM | #31 |
Penultimate Amazing
Join Date: Oct 2006
Location: Dog House
Posts: 26,122
|
Better save it, he might purge his failed physics lesson if he gains knowlege. http://www.youtube.com/watch?v=l0jbDeSavyU
|
2nd July 2011, 04:56 PM | #32 |
Master Poster
Join Date: May 2009
Posts: 2,847
|
Ok, I don't have time to read it all now, but it looks like a howler.
|
__________________
DoYouEverWonder - Engineers and architects don't have to design steel buildings not to collapse from gravity. They already conquered gravity when they built it. - Professional Wastrel |
|
2nd July 2011, 04:57 PM | #33 |
NWO Master Conspirator
Join Date: Mar 2003
Posts: 59,856
|
|
__________________
Vive la liberté! |
|
2nd July 2011, 04:58 PM | #34 |
Muse
Join Date: Apr 2008
Posts: 686
|
thanks for the answers, it's been fun. Join in on youtube for extra entertainment. That's where the mass and velocity of the 9/11 truth is running around claiming science proves their conspiracies.
|
2nd July 2011, 04:58 PM | #35 |
Philosopher
Join Date: Nov 2010
Posts: 7,296
|
Would he like to start talking about kinetic energy instead?
|
__________________
What do Narwhals, Magnets and Apollo 13 have in common? Think about it.... |
|
2nd July 2011, 05:08 PM | #36 |
Penultimate Amazing
Join Date: Oct 2006
Location: Dog House
Posts: 26,122
|
He is the person in the video, it is show biz. He does the FKN, like news, and he does FNP, like Balsamo physics. I think he is the brains behind ... http://fknnewz.com/
And remember...
Quote:
|
2nd July 2011, 05:16 PM | #37 |
Banned
Join Date: Mar 2011
Location: Patriot Nation
Posts: 22,131
|
|
2nd July 2011, 05:19 PM | #38 |
Muse
Join Date: Apr 2008
Posts: 686
|
beachnut
since i'm none too smart on physics (forgive me for i was behind the bike sheds smoking when i should have been in class) but what is it you find funny about "A is = to v when impact mass is stationary". You can tell why i needed help in debating those who claim science as evidence of the 9/11 conspiracy |
2nd July 2011, 05:21 PM | #39 |
Muse
Join Date: Apr 2008
Posts: 686
|
|
2nd July 2011, 05:26 PM | #40 |
NWO Kitty Wrangler
Join Date: May 2006
Posts: 29,690
|
Okay, just found it, and noticed someone () paraphrasing me! He responds:
Quote:
Here's a real copy of that link: http://easycalculation.com/physics/c...c-velocity.php I'd love to see what part of that page he thinks supports his "calculation". Above, I was referring to the A = (v - vo)/t equation. The only way a vo of 154 m/s can equal an A of -154 m/s/s is if v = 0 m/s and t = 1 s, which is a calculation so stupid that again, I assert that he'll never understand why it's wrong. There are at least two ridiculous assumption here: that the impact with the post will stop the plane dead, and that this stoppage will take a full second to occur. There's no other way he could justify this "calculation". |
__________________
Obviously, that means cats are indeed evil and that ownership or display of a feline is an overt declaration of one's affiliation with dark forces. - Cl1mh4224rd |
|
Thread Tools | |
|
|