時差N小時:圓周率的奧妙

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Y: Don. Don?

D: What?

Y: What are you doing?

D: I was trying to break the record for memorizingpi. Now I'll have to start over.

Y: Memorize pi? Oh yeah, I remember that from 7th grade geometry. But how can youmemorize pi? We usually abbreviate it as 3.14, but the numbers just keep going after thedecimal point.

D: I'm trying to memorize as many numbers as I can. The record is 42,000 decimal places.

Y: Wow. You're really going to try to memorize that much? Why? What is pi, anyway.

D: It's only one of the most fascinating numbers in the history of mathematics. It soundssimple: Pi equals the circumference of a circle divided by its diameter. No matter how largeor small the circle, the ratio always equals pi.

Y: That's interesting.

D: Yes, and it has been for over 4000 years. The Babylonians were the first to approximate pi,and ever since, mathematicians have come up with ways of figuring it more accurately. Inmodern times we've used supercomputers to calculate pi to billions of decimal places.

Y: That's really something. But what's all the excitement about? I mean, what is pi used for?

D: It's used to measure the length of arcs and other curves and to determine the area ofsectors and other curves. It's also used to measure the volume of solids. For instance, if you'rea rocket scientist trying to calculate the fuel capacity of a cylindrical fuel tank, pi's your guy.

Y: Cool.

D: Now, if you'll excuse me, I've got a record to break.

Y: Good luck.

D: 3.1415 9265 3589 7932 3846 . . .

【生詞注釋】

memorize v.記住, 記下

pi n.圓周率

start over 重新開始

geometry n. 幾何學(xué)

decimal point 小數(shù)點

fascinating adj.迷人的

curve n.曲線

sector n.扇形

D: 3.1415926535 . . .

Y: Don. Don?

D: 什么事?

Y: 你在干嗎?

D: 我正努力背圓周率來打破紀(jì)錄?，F(xiàn)在我必須重新開始。

Y: 背圓周率?我記得在7年級學(xué)幾何時背的。你是如何背的?我們通常縮進至3.14，但是小數(shù)點后還有很多數(shù)。

D: 我正努力盡量多背些。紀(jì)錄是背到小數(shù)點后第42,000位。

Y: 你真準(zhǔn)備背那么多?為什么?到底什么是圓周率。

D: 圓周率是數(shù)學(xué)史上最吸引人的數(shù)字。它聽起來很簡單，圓的直徑除以周長就等于圓周率。無論圓多大或多小，結(jié)果都是一樣的。

Y: 很有意思。

D: 圓周率已經(jīng)有4千年歷史了啦。巴比倫人首個得到的數(shù)字接近圓周率，從那以后，數(shù)學(xué)家用各種方法來準(zhǔn)確計算。現(xiàn)在我們用超級計算機來計算元中旅到小數(shù)點上億后。

Y: 真有意思。有什么值得高興的?圓周率用來干什么?

D:用來計算弓形和各種曲線的長度來決定扇形的面試和其他曲線。圓周率也用來測量固體的體積。比如，如果你是火箭專家，正準(zhǔn)備計算圓柱形燃料容器的燃料體積，就得用到圓周率。

D: 酷。

Y：打不起，我得準(zhǔn)備打破記錄了。

D: 好運。

Y：3.1415 9265 3589 7932 3846 . . .