Can you solve the airplane riddle? - Judd A. Schorr

6,934,835 views ・ 2016-12-01

TED-Ed


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翻译人员: Sunny Wu 校对人员: Yulin Li
00:07
Professor Fukanō, the famous eccentric scientist and adventurer,
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著名的古怪科学家和探险家Fukanō教授
00:11
has embarked on a new challenge:
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开始了一项新的挑战
00:13
flying around the world nonstop in a plane of his own design.
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用他自己设计的飞机进行一次环绕世界的无停靠飞行
00:17
Able to travel consistently at the incredible speed of one degree longitude
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这架飞机能够持续以每分钟飞过每一经度的高速
00:22
around the equator per minute,
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沿着赤道飞行
00:24
the plane would take six hours to circle the world.
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只需要6小时就可以环绕世界一周
00:28
There's just one problem:
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只有一个问题需要克服:
飞机只能携带18万升的燃料
00:30
the plane can only hold 180 kiloliters of fuel,
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00:34
only enough for exactly half the journey.
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这个量只够完成一半旅程
00:37
Let's be honest.
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所以还是现实点吧
00:38
The professor probably could have designed the plane to hold more fuel,
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教授或许可以设计一种能携带更多燃料的飞机
00:41
but where's the fun in that?
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但那就没意思了
00:43
Instead, he's devised a slightly more elaborate solution:
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相反,他想出了一种更烧脑的解决方案
00:47
building three identical planes for the mission.
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为这项任务建造三架一模一样的飞机
00:51
In addition to their speed,
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除了高速之外,
教授还给它们装备了其他绝妙的功能
00:53
the professor's equipped them with a few other incredible features.
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00:56
Each of the planes can turn on a dime
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每一个飞机能够在很小的空间里转弯
并立刻把任意量的燃料 转移到在空中的其它飞机内
00:59
and instantly transfer any amount of its fuel to any of the others in midair
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且不需要减速
01:04
without slowing down,
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01:05
provided they're next to each other.
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只要他们相邻而飞
01:07
The professor will pilot the first plane,
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教授驾驶第一架飞机
01:09
while his two assistants Fugōri and Orokana will pilot each of the others.
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他的两个助手Fugōri和Orokana分别驾驶另外两架飞机
01:14
However, only one airport, located on the equator,
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然而,只有一个赤道上的机场
01:18
has granted permission for the experiment,
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许可了这项实验
01:20
making it the starting point,
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以机场为起点
终点
01:22
the finish line,
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01:23
and the only spot where the planes can land,
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以及飞机降落
01:25
takeoff,
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起飞
01:26
or refuel on the ground.
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和地面加油的唯一地点
01:28
How should the three planes coordinate
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这三架飞机应该如何配合
01:30
so the professor can fly continuously for the whole trip and achieve his dream
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才能使教授在每一架飞机 都不会耗尽燃料或坠毁的情况下
01:35
without anyone running out of fuel and crashing?
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持续飞行完全程以实现他的梦想呢?
01:38
Pause here if you want to figure it out for yourself.
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如果您需要浏览本页,请暂停
01:42
Answer in: 3
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答案:3
01:43
Answer in: 2
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答案:2
01:44
Answer in: 1
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答案:1
根据教授的计算
01:46
According to the professor's calculations,
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01:48
they should be able to pull it off by a hair.
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他们应该可以勉强完成这个任务
关键就在于把每个助手的助力最大化
01:51
The key is to maximize the support each assistant provides,
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不浪费每一升燃料
01:55
not wasting a single kiloliter of fuel.
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01:58
It also helps us to think symmetrically
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对称地思考这段旅程可以帮助我们理解
02:01
so they can make shorter trips in either direction
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他们可以从起点的两个方向进行短途飞行
02:03
while setting the professor up for a long unsupported stretch in the middle.
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同时让教授从中途开始进行无供给的长途飞行
02:08
Here's his solution.
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解决方案是这样的
02:09
All three planes take off at noon flying west,
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三架飞机都在正午起飞向西飞行
每架飞机装载18万升燃料
02:13
each fully loaded with 180 kiloliters.
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02:16
After 45 minutes, or one-eighth of the way around,
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45分钟后,也就是1/8的行程后
02:19
each plane has 135 kiloliters left.
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每架飞机剩13.5万升燃料
02:23
Orokana gives 45 to the professor and 45 to Fugōri,
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Orokana给教授和Fugōri分别输送了4.5万升
02:27
fully refueling them both.
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使他们的飞机加满油
02:29
With her remaining 45, Orokana returns to the airport
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Orokana用她余下的4.5万升返回机场
02:33
and heads to the lounge for a well-deserved break.
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并到休息室好好休息一番
02:36
45 minutes later, with one-quarter of the trip complete,
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45分钟后,1/4的行程飞完
02:39
the professor and Fugōri are both at 135 kiloliters again.
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教授和Fugōri的燃料又都剩下13.5万升
Fugōri给教授传输了4.5万升
02:45
Fugōri transfers 45 into the professor's tank,
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02:48
leaving himself with the 90 he needs to return.
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给自己留下9万升用来返回机场
02:52
Professor Fukanō stretches and puts on his favorite album.
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Fukanō教授可以伸伸懒腰听听音乐了
02:55
He'll be alone for a while.
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他要自己度过接下来的一段时间
02:57
In the meantime, Orokana has been anxiously awaiting Fugōri's return,
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与此同时, Orokana正焦急地等Fugōri回来
03:01
her plane fully refueled and ready to go.
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她的飞机已经加满油并准备出发了
03:05
As soon as his plane touches the ground, she takes off, this time flying east.
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Fugōri的飞机降落的同时,她立刻起飞,这次向东飞行
03:10
At this point, exactly 180 minutes have passed
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到目前为止,已经过去了180分钟
教授正好完成了一半的旅程
03:14
and the professor is at the halfway point of his journey
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03:17
with 90 kiloliters of fuel left.
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还剩下9万升燃料
来完成接下来90分钟的飞行
03:20
For the next 90 minutes,
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03:21
the professor and Orokana's planes fly towards each other,
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教授和Orokana的飞机相对而飞
03:24
meeting at the three-quarter mark.
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在行程的四分之三处相遇
03:27
Just as the professor's fuel is about the run out,
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就在教授的燃料将要耗尽时
03:29
he sees Orokana's plane.
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他看到了Orokana的飞机
03:32
She gives him 45 kiloliters of her remaining 90,
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Orokana从余下的9万升燃料中给了教授4.5千升
03:35
leaving them with 45 each.
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让两架飞机都有4.5万升
03:37
But that's just half of what they need to make it to the airport.
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但这只够完成接下来的半程
幸运的是,这时Fugōri已经加好油起飞了
03:41
Fortunately, this is exactly when Fugōri, having refueled, takes off.
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03:46
45 minutes later, just as the other two planes are about to run empty,
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45分钟后,就在另两架飞机燃料要耗尽时
03:51
he meets them at the 315 degree point
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Fugōri在315度处遇见了他们
03:54
and transfers 45 kiloliters of fuel to each, leaving 45 for himself.
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并给他们分别传输了4.5万升,给自己留下4.5万升
03:59
All three planes land at the airport just as their fuel gauges reach zero.
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三架飞机在机场降落时,燃料正好耗尽
04:04
As the reporters and photographers cheer,
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记者们和摄影师们开始欢呼
教授承诺他的飞机很快会作为商用航班投入使用
04:07
the professor promises his planes will soon be available for commercial flights,
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04:11
just as soon as they figure out how to keep their inflight meals
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只需等他们研究出怎么样在飞机上用餐 才不会撒得到处都是
04:14
from spilling everywhere.
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就是时候了!
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