Tom Roger’s Insultingly Stupid Movie Physics teaches basic science principles in one of the most entertaining ways possible: by illustrating the ways in which elements of popular Hollywood films are hopelessly out of line with the physical laws that exist in our universe. Topics covered include the laws of motion, gravitation, vehicles, the behaviour of weapons, relativity, extreme weather, space travel, and more.
While the book may seem whimsical, Rogers makes the important point that movies are a form of vicarious experience for people. For most of us, they have provided most of our ‘knowledge’ about firearms, knives, the extreme operation and destruction of vehicles, the destruction of buildings, etc. By consistently misrepresenting these things, films leave people ill-equipped to understand the phenomena in the real world.
In addition to this, Rogers’ book includes a detailed debunking of two conspiracy theories partially fuelled by a poor understanding of physics. In the first, he discusses the physics of the JFK assassination, in the context of the popular film. He argues that the official account is convincing for a number of reasons, and that the film has helped to entrench a serious misunderstanding in the minds of many Americans. The second conspiracy theory – that the World Trade Centre was destroyed using explosives planted inside – is similarly based in a bad understanding of physics, and similarly damaging in terms of the way in which it colours people’s thinking.
The kind of people who take delight in outsmarting the people who make movies will probably find this book very entertaining. Those trying to teach physics concepts may also find it useful as a mechanism for engaging people and having them explore ideas in an imaginative but realistic way.
“that the World Trade Centre was destroyed using explosives planted inside – is similarly based in a bad understanding of physics”
Now that isn’t really true is it. Is a bad understanding of physics the cause of a conspiracy theory? There are plenty of people who think WTC was controlled who know much more about physics than most everyone who believes the standard account. To say some theory “comes from” a good or bad understanding of physics is really to mis understand where conspiracy theories come from. Almost everyone doesn’t understand the physics well enough to evaluate the journals this is seriously discussed in. Appeals to specialized physics are very close to the fallacy of appeal to authority.
Why power systems gain from terrorist attacks and other disasters, but why this is not itself a good argument for 9/11 being produced internally.
Why the evidence produced for 911 truth is essentially worthless.
Why the 9/11 truth movement serves a similar purpose as the JFK assassination – take energy away from serious issues towards ones that don’t matter – (skip to 7:18)
http://www.youtube.com/watch?v=m7SPm-HFYLo
I think the so-called ‘911 truth’ movement derives a lot of strength from incorrect beliefs about physics. For instance, that the fact that jet fuel doesn’t burn hot enough to melt steel means the fuel from the planes could not have made the towers collapse. Roger’s book does a good job of describing the phenomena responsible, including the softening of the steel, and the ways in which the drooping floors pulling on the vertical steel supports in the outside walls led to a catastrophic failure. It’s not really ‘specialized physics’ if it can be explained effectively by analogy in a lighthearted book poking fun at the movies.
Buckling
From Wikipedia, the free encyclopedia
In engineering, buckling is a failure mode characterized by a sudden failure of a structural member subjected to high compressive stresses, where the actual compressive stress at the point of failure is less than the ultimate compressive stresses that the material is capable of withstanding. This mode of failure is also described as failure due to elastic instability. Mathematical analysis of buckling makes use of an axial load eccentricity that introduces a moment, which does not form part of the primary forces to which the member is subjected.
I think the most powerful argument is not based on softening of the steel, but the rate of fall. The buildings fell slower than the freefall rate for about 4 seconds, after which they fell at the free fall accelerative rate. Since the building above was not more massive than the building below, I have not heard a convincing physics explanation of why the building should have collapsed the building at or near the freefall rate, and not at a significantly reduced speed.
XKCD on conspiracy theories
Why Did the World Trade Center Collapse? Science, Engineering, and Speculation
Thomas W. Eagar and Christopher Musso
With a 700 Pa floor design allowable, each floor should have been able to support approximately 1,300 t beyond its own weight. The total weight of each tower was about 500,000 t.
As the joists on one or two of the most heavily burned floors gave way and the outer box columns began to bow outward, the floors above them also fell. The floor below (with its 1,300 t design capacity) could not support the roughly 45,000 t of ten floors (or more) above crashing down on these angle clips. This started the domino effect that caused the buildings to collapse within ten seconds, hitting bottom with an estimated speed of 200 km per hour. If it had been free fall, with no restraint, the collapse would have only taken eight seconds and would have impacted at 300 km/h. It has been suggested that it was fortunate that the WTC did not tip over onto other buildings surrounding the area. There are several points that should be made. First, the building is not solid; it is 95 percent air and, hence, can implode onto itself. Second, there is no lateral load, even the impact of a speeding aircraft, which is sufficient to move the center of gravity one hundred feet to the side such that it is not within the base footprint of the structure. Third, given the near free-fall collapse, there was insufficient time for portions to attain significant lateral velocity. To summarize all of these points, a 500,000 t structure has too much inertia to fall in any direction other than nearly straight down.