41–50 of 50 posts
If you're curious about the engineering that goes into a large Lego structure, James May ("Captain Slow" of Top Gear fame) built an entire house out of Legos. http://www.youtube.com/watch?v=qR2YqMrS_pM It's an hour long story, but if you want to skip to the final product: http://www.youtube.com/watch?v=qR2YqMrS_pM#t=2600s
If you're curious about the engineering that goes into a large Lego structure, James May ("Captain Slow" of Top Gear fame) built an entire house out of Legos. http://www.youtube.com/watch?v=qR2YqMrS_pM It's an hour long story, but if you want to skip to the final product: http://www.youtube.com/watch?v=qR2YqMrS_pM#t=2600s
Its been a while since I watched that episode, but that was built with a steel superstructure surrounded by lego right? The lego was only partially load-bearing?
Wow, bbc is really hard up for news huh? I really loved this quote: '"... it's the typical height at which people ski in the Alps," Ian Johnston says (though many skiers also ski at lower altitudes).' Really? I would never have guessed...
so is hn it seems. these days hn is becoming a day-delayed digg list.
Both of these showing up just at the inflection point of the Christmas shopping season.
Good game, Lego.
Ah, but that's not quite the issue, if the question is how high of a tower you can build.
If a tower is 3.5 km tall, then the lower 100m (to pull a number out of the air) are all supporting pretty much the same weight. And that 100m is about ... 10,000 bricks thick? If one of those bricks goes, then the tower goes. So what you want to know is not the average strength of a brick, but the expected strength of the weakest brick out of 10,000. I imagine that's significantly less.
Exercise for the reader: Given the probability distribution of brick strength, how do we compute the height at which we expect a one-brick-wide tower to fail? (Assume that vertical compression of bricks is the only issue; there are no lateral forces, the tower is perfectly balanced, etc.)
Wow, bbc is really hard up for news huh? I really loved this quote: '"... it's the typical height at which people ski in the Alps," Ian Johnston says (though many skiers also ski at lower altitudes).' Really? I would never have guessed...
More or Less is a great program that introduces statistics to current affairs topics and listener questions. This was in response to a listener question. It being on the news is the usual BBC thing of using BBC news as an advertising medium for BBC shows.
Speaking as an ex-aerospace-stress analyst, I found the article lacking. 2x2 Lego bricks individually fail by plastic deformation. The weight of an unreasonably tall tower could cause it, but we know that such an unreasonably tall tower can't exist because of stability concerns. So: what actually limits the height of a Lego tower? Elastic buckling, or some other kind of buckling, or is it something weird because of t…
As an ex-civil engineer, this would be an awesome, but expensive competition for freshman engineering students. I actually remember a problem set containing questions like "how tall a tower" ignoring things like stability for various materials. Backing out some numbers from the piece, the 2x2 held 950 lbs, which is roughly 1000 lbs in 1/2"x1/2", or 4000psi. That's roughly the strength of ordinary unreinforced concret…
Earlier quoted context omitted.
As an ex-civil engineer, this would be an awesome, but expensive competition for freshman engineering students. I actually remember a problem set containing questions like "how tall a tower" ignoring things like stability for various materials. Backing out some numbers from the piece, the 2x2 held 950 lbs, which is roughly 1000 lbs in 1/2"x1/2", or 4000psi. That's roughly the strength of ordinary unreinforced concret…
SO the rules of Lego-tower-building have to have the slope of the sides of the tower steeper than the angle of repose of a mass of bricks, eh? Otherwise, it's just a pile, not a tower.
And for extra credit, the tower should survive a run on the shake table.
Speaking as an ex-aerospace-stress analyst, I found the article lacking. 2x2 Lego bricks individually fail by plastic deformation. The weight of an unreasonably tall tower could cause it, but we know that such an unreasonably tall tower can't exist because of stability concerns. So: what actually limits the height of a Lego tower? Elastic buckling, or some other kind of buckling, or is it something weird because of t…
As an ex-civil engineer, this would be an awesome, but expensive competition for freshman engineering students. I actually remember a problem set containing questions like "how tall a tower" ignoring things like stability for various materials. Backing out some numbers from the piece, the 2x2 held 950 lbs, which is roughly 1000 lbs in 1/2"x1/2", or 4000psi. That's roughly the strength of ordinary unreinforced concret…
So why can't we build a space elevator?
If you're curious about the engineering that goes into a large Lego structure, James May ("Captain Slow" of Top Gear fame) built an entire house out of Legos. http://www.youtube.com/watch?v=qR2YqMrS_pM It's an hour long story, but if you want to skip to the final product: http://www.youtube.com/watch?v=qR2YqMrS_pM#t=2600s
Earlier quoted context omitted.
As an ex-civil engineer, this would be an awesome, but expensive competition for freshman engineering students. I actually remember a problem set containing questions like "how tall a tower" ignoring things like stability for various materials. Backing out some numbers from the piece, the 2x2 held 950 lbs, which is roughly 1000 lbs in 1/2"x1/2", or 4000psi. That's roughly the strength of ordinary unreinforced concret…
> If you taper the tower with an exponential curve, 1/e^x, the pressure on the bottom of the tower can be constant as you increase the both the footprint and the height. So why can't we build a space elevator?
Earth's radius is 4k miles. Geostationary orbit is ~25k. Space elevators IIRC, are proposed for ca 60k miles out. Assuming a 10-20x height/width ratio, the base would be 3-6k miles on a side. Even just getting to geostationary orbit would require a mountain with a base the size of a continent.