《那些古怪又让人忧心的问题》第101期:乐高大桥(1)
LEGO BRIDGE
Q. How many Lego bricks would it take to build a bridge capable of carrying traffic from London to New York? Have that many Lego bricks been manufactured?
Q．要想用乐高积木搭一座连接纽约和伦敦的大桥需要多少积木？已经生产出来的乐高积木数量够建造这么一座大桥吗？——Jerry Petersen
——杰瑞•彼得森
A. LET'S START WITH A less ambitious goal.
A．野心先不要这么大。Making the connection
连接两座城市There have certainly been enough Lego1 bricks to connect New York and LEGO2 units, New York and London are 700 million studs apart. That means that if you arranged bricks like this . . .
全世界当然有足够连接纽约和伦敦的Lego1积木。如果用LEGO2“单体”来作为衡量标准的话，纽约和伦敦相距7亿块单体。这意味着如果你像这样搭积木……. . . it would take 350 million of them to connect the two cities. The bridge wouldn't be able to hold itself together or carry anything bigger than a LEGO®3 minifig, but it's a start.
……则会需要3.5亿块积木。不过造出来的桥连自身的完整性都不能保证，而且任何比LEGO®3小人大的东西都放不上去。但这是一个很不错的开头。There have been over 400 billion Lego4 pieces produced over the years. But how many of those are bricks that would help with a bridge, and how many are little helmet visors that get lost in the carpet?
全世界已经生产出来的Lego4积木超过4000亿块，但其中又有多少是可以拿来建造这座乐高大桥的砖块，又有多少是丢失在地毯当中的乐高小人护目镜呢？Let's assume we're building our bridge out of the most common LeGo5 piece-the 2x4 brick.
假设我们用的是最普通的2×4 LeGo5积木。Using data provided by Dan Boger, Lego6 kit archivist and operator of the Lego data site, I've come up with the following rough estimate: 1 out of every 50 to 100 pieces is a 2x4 rectangular brick. This suggests there are about 5–10 billion 2x4 bricks in existence, which is more than enough for our one-block-wide bridge.
丹•博格是一位Lego6套装档案保管员，同时也是乐高数据网站的运营专员，用他整理出来的数据我粗略估计了一下：每50～100块乐高积木中就有一块2×4的长方形积木。这意味着全世界一共有50亿～100亿块2×4乐高积木，这些积木足够建造我们那个一块积木宽的乐高大桥了。Supporting cars
承载汽车Of course, if we want to support actual traffic, we'll need to make the bridge a little wider.
当然了，如果我们想让正常的汽车能够开上乐高大桥，那么大桥需要变得更宽一些。We probably want to make the bridge float. The Atlantic Ocean is deep,[citation needed] and we want to avoid building 3-mile-high pylons out of Lego bricks if we can.
我们可能还想让乐高大桥浮起来。大西洋很深，所以我们希望尽可能别建造一个5千米高的乐高桥塔。Lego bricks don't make a watertight seal when you connect them together,7 and the plastic used to make them is denser than water. That's easy enough to solve; if we put a layer of sealant over the outer surface, the resulting block is substantially less dense than water.
一块块拼起来的乐高积木并不具有防水性7，而且制作乐高积木的塑料密度大于水。这个问题很好解决：我们在外表面涂一层密封材料，这样整个积木块的密度就比水小了。For every cubic meter of water it displaces, the bridge can carry 400 kg. A typical passenger car weighs a little under 2000 kg, so our bridge will need a minimum of 10 cubic meters of Lego supporting each passenger car.
每排开1立方米的水，我们的乐高大桥能够浮起400千克的物体。一辆普通的私家车质量接近2000千克，所以每开上去一辆车，乐高大桥的体积就至少要增加10立方米。If we make the bridge a meter thick and 5 meters wide, then it should be able to stay afloat without any trouble-although it might ride low in the water-and be sturdy enough to drive on.
如果我们造出1米厚5米宽的大桥，它自身浮在水面上应该没什么问题——虽然突出海平面只有一点点距离——汽车开在上面也会很稳当。Legos8 are quite strong; according to a BBC investigation, you could stack a quarter of a million 2x2 bricks on top of each other before the bottom one collapsed.9
Legos8积木强度非常高。根据英国广播公司（BBC）的研究结果，如果你把2×2的乐高积木一块一块往上叠，需要叠25万块积木才能让最下面那块积木崩溃。9The first problem with this idea is that there aren't nearly enough Lego blocks in the world to build this kind of bridge. Our second problem is the ocean.
这种想法遇到的第一个问题是世界上没有足够的乐高积木来建造出这种样式的乐高大桥。第二个问题和海洋有关。
