This is very Five-Thrity-Eight-ish, I love it!
It reminded me of Randall Munroe's "What If?" work. I'd love to see him critique the author's and our comments. With stick figures! :)
Could You See the Curvature of the Earth in This Airport?
21–30 of 36 posts
Re: Could You See the Curvature of the Earth in This Airport?
#22a couple of broken reference links in the article; never forget "https://" when adding a link.
Re: Could You See the Curvature of the Earth in This Airport?
#23I don't like his method of measuring the curvature distance. I think it will be very difficult to align a local to the local tangent of the earth's surface. Over a distance of 700m, the earth's surface deviates by about 4cm. This means we would have to align our laser to within 50 microradians in order to accurately measure the deviation of the earth's surface. Further more, his two beam system is setup using two las…
Your approach mirrors what mine would have been. If the curvature of the earth can be measured over 725 meters, then to me, it's inconsequential whether or not that is detectable within this man-made construct.
That isn't to impugn the question, or the method, but that I'm less interested in whether the architects adjusted each each to be 4cm higher than they would need to be or not. Even if the airport were built over the course of 5 meters, in which the curvature would be (effectively) undetectable, the airport itself, being man-made, may exhibit irregularities caused by human error, shifting ground, variable bedrock, etc.
Regardless, the article was fantastically fun to read, as was your post.
Re: Could You See the Curvature of the Earth in This Airport?
#24One could also use the bowling ball to answer the level vs straight question. Ignoring such nuisances as friction, on a straight floor, a ball let loose would roll towards the center of the hall, and oscillate around it. In practice, it may be possible to somewhat reliably measure a difference in deceleration rolling the ball towards an end of the hall vs towards its center. And of course, if one also has a scale, th…
> And of course, if one also has a scale, the weight of the ball can be used to see whether the floor is level. Can you elaborate on this? Why would the weight be different if non-level? Unless you're meaning that the center-of-mass of the ball would be ~2 centimeters further from the center-of-mass of the Earth and 1/r^2 means a decrease?
The 1/r2 one. Going even more esoteric, I guess, in an idealized world, one can measure the deformation of the bowling ball due to gravity, and check whether it changes across the hall.
Re: Could You See the Curvature of the Earth in This Airport?
#25Relevant question from Reddit's AskScience section (which is heavily moderated and thus very high-quality): > How (if at all) do architects of large buildings deal with the Earth's curvature? http://www.reddit.com/r/askscience/comments/29jrhq/how_if_at...
It seems to me that unless they went out of their way to make it 'straight' local craftsmen are going to use a level any time they set something like a floor or wall, and therefore the building will follow the curvature of the earth. Above they speak of linear accelerators and how they have to make sure to keep things straight, rather than level. I doubt they'd go to that effort for an airplane terminal.
Re: Could You See the Curvature of the Earth in This Airport?
#26Earlier quoted context omitted.
This is a fact "borrowed" from my Web site without attribution. Here's the original: http://arachnoid.com/carnival/index.html#Vertical In the linked article, we also find this graphic used to make another point -- horizon distance: http://datagenetics.com/blog/june32012/globe.png Here's the original, from my Web site: http://arachnoid.com/carnival/resources/horizon_distance.png Look familiar?
It's familiar because it's a not uncommon comment. Well, except that most such comments refer to the Verrazano-Narrows Bridge, which has a longer span than the Golden Gate. For examples: - Guinness Book of World Records (1973) made it with the Verrazano-Narrows Bridge - http://books.google.com/books?ei=93b7U_XoBuT5yQPkqYGIBQ&hl=s... - So did Henry Petroski in Engineers of Dreams: Great Bridge Builders and the Spannin…
What tools are you using to locate these sources?
Re: Could You See the Curvature of the Earth in This Airport?
#27Privacy Badger, RequestPolicy, and AdBlock Edge all puked on this Wired page. None of the calculations would load. :(
Re: Could You See the Curvature of the Earth in This Airport?
#28I live in ATL and now I very much want to go to the airport at 3am and test this.
Re: Could You See the Curvature of the Earth in This Airport?
#29Offer the building's super the barometer, if in exchange he'll tell you how tall the building is. [1]
Did the author of the article not bother to investigate the actual answer?
Re: Could You See the Curvature of the Earth in This Airport?
#30Earlier quoted context omitted.
No it doesn't. Not at all, except insofar as that basic sketch is depicted in a zillion trigonometry textbooks and has been for well longer than you've been alive. The basic idea is pretty obvious. People have been computing "astounding facts" attributable to the Earth's curvature for thousands of years. Golden Gate Bridge is a pretty obvious choice for computing the tangible spread of two apparently parallel towers:…
> Oh, and your sketch is wrong. The two lines labeled " R " aren't the same length. lutusp's diagram is the arachnoid one. His labels are correct, it's the datagenetics one that has apparently incorrect labeling. The dashed red line is not R in length, but R + h, which is not clearly indicated though the apparent intent. The dashed line should stop at the circle and change color or something to indicate a second line…
Mea culpa. Mixed 'em up in my bafflement of his assertion of ownership over a classic mathematical example.