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硬核科普大合集 [Yìng hé kēpǔ dà héjí] – Collection of hard core science popularization (399 videos)

1.

海市蜃楼中的景象,为什么有的正立,有的倒立? [Hǎishìshènlóu zhōng de jǐngxiàng, wèishéme yǒu de zhèng lì, yǒu de dàolì?] – Why do some of the scenes in the mirage stand upright and some stand upside down?
景象神奇有正有倒
海市蜃楼是什么原理?
[Jǐngxiàng shénqí yǒu zhèng yǒu dào hǎishìshènlóu shì shénme yuánlǐ?] – The sight is magical
What is the principle of mirage?
周哲 -- 科普视频创作人 [Zhōu zhé — kēpǔ shìpín chuàngzuò rén] – Zhou Zhe -Popular science video creator

最近多地都看到了海市蜃楼的景象 [Zuìjìn duō de dōu kàn dàole hǎishìshènlóu de jǐngxiàng] – I’ve seen mirages in many places recently.
诶那么海事蜃楼是什么原理?[Éi nàme hǎishì shènlóu shì shénme yuánlǐ?] – Hey, what is the principle of the mirage?
今天我们就来聊一聊这个问题。[Jīntiān wǒmen jiù lái liáo yī liáo zhège wèntí.] – Today we will talk about this issue.
首先我们先要来说一个常见的现象。[Shǒuxiān wǒmen xiān yào lái shuō yīgè chángjiàn de xiànxiàng.] – First, let’s talk about a common phenomenon.
那就是光的折射。[Nà jiùshì guāng de zhéshè.] – That is the refraction of light.
一支笔在水中的这个部分看起来它就像变弯了一样。[Yī zhī bǐ zài shuǐzhōng de zhège bùfèn kàn qǐlái tā jiù xiàng biàn wānle yīyàng.] – This part of a pen in water looks like it’s bent.
这就是我们熟悉的光的折射现象。[Zhè jiùshì wǒmen shúxī de guāng de zhéshè xiànxiàng.] – This is the phenomenon of refraction of light that we are familiar with.
可是我们都知道光是沿直线传播的。[Kěshì wǒmen dōu zhīdào guāng shì yán zhíxiàn chuánbò de.] – But we all know that light travels in straight lines.
为什么这个笔变弯了呢?[Wèishéme zhège bǐ biàn wānle ne?] – Why is this pen bent?
其实光沿直线传播这句话是有个前提的。[Qíshí guāng yán zhíxiàn chuánbò zhè jù huà shì yǒu gè qiántí de.] – In fact, there is a premise that light travels in a straight line.
那就是在均匀介质当中。[Nà jiùshì zài jūnyún jièzhì dāngzhōng.] – That is in a homogeneous medium.

那就是在均匀介质当中
或者在真空当中
光才会沿直线传播
但如果光要是从折射率
Nà jiùshì zài jūnyún jièzhì dāngzhōng huòzhě zài zhēn kòng dāngzhōng guāng cái huì yán zhíxiàn chuánbò dàn rúguǒ guāng yàoshi cóng zhéshè lǜ

https://youtube.com/watch?v=Ll53m_Dpv6w%3Fstart%3D30


如何站在上帝视角给银河系拍一张全景照片?Rúhé zhàn zài shàngdì shìjiǎo gěi yínhéxì pāi yī zhāng quánjǐng zhàopiàn? – How to take a panoramic photo of the Milky Way from the perspective of God?

最近事件视界望远镜 EHT 公布了银河系中心黑洞的照片。有网友问那我们银河系的整体照片是怎么拍的呢?Zuìjìn shìjiàn shìjiè wàngyuǎnjìng (EHT) gōngbùle yínhéxì zhōngxīn hēidòng de zhàopiàn. Yǒu wǎngyǒu wèn nà wǒmen yínhéxì de zhěngtǐ zhàopiàn shì zěnme pāi de ne? – The Event Horizon Telescope (EHT) recently released images of the black hole at the center of the Milky Way. Some netizens asked how the overall photo of our Milky Way was taken?

看这个视角 | 我们是有什么银河系外的卫星吗?

好问题 | 答案是没有 | 目前已经飞行最运的人造物体是旅行者一号 | 但旅行者一号也仅仅是飞行了一百五十多个日地距离左右 | 也就是一百五十 AU | 宇宙的尺度通常都是用光年来衡量的 | 多少 AU 等于一光年呢?

Kàn zhège shìjiǎo | wǒmen shì yǒu shé me yínhéxì wài de wèixīng ma? Hào wèntí | dá’àn shì méiyǒu | mùqián yǐjīng fēixíng zuì yùn de rénzào wùtǐ shì lǚxíng zhě yī hào | dàn lǚxíng zhě yī hào yě jǐnjǐn shì fēixíngle yībǎi wǔshí duō gè rì de jùlí zuǒyòu | yě jiùshì yībǎi wǔshí AU | yǔzhòu de chǐdù tōngcháng dōu shì yòng guāng niánlái héngliáng de | duōshǎo AU děngyú yī guāng nián ne?

– Look at this perspective | Are we some extra-galactic satellite? Good question | The answer is no | The most fortunate man-made object that has flown so far is Voyager 1 | But Voyager 1 has only flown more than 150 sun-earth distances | That is 150 AU | The universe is usually measured in light-years | How many AUs are equal to one light-year?

大概是六万三千多个 AU (天文单位)才等于一光年 | 所以按照光年的尺度来看 | 旅行者一号才算刚刚出发 | 刚刚离开家门 | 而这张照片中的视角位置 | 至少有银河系半径那么远 | 也就是大概有五万都九万光年这么远 | 也就是说我们是没有办法发射一个探测器 | 去拍摄一张银河系的照片的 | 所以答案只能是 | 这张照片是科学家想象出来的。Dàgài shì liù wàn sānqiān duō gè AU (tiānwén dānwèi) cái děngyú yī guāng nián | suǒyǐ ànzhào guāng nián de chǐdù lái kàn | lǚxíng zhě yī hào cái suàn gānggāng chūfā | gānggāng líkāi jiāmén | ér zhè zhāng zhàopiàn zhōng de shìjiǎo wèizhì | zhìshǎo yǒu yínhéxì bànjìng nàme yuǎn | yě jiùshì dàgài yǒu wǔ wàn dōu jiǔ wàn guāng nián zhème yuǎn | yě jiùshì shuō wǒmen shì méiyǒu bànfǎ fāshè yīgè tàncè qì | qù pāishè yī zhāng yínhéxì de zhàopiàn de | suǒyǐ dáàn zhǐ néng shì | zhè zhāng zhàopiàn shì kēxuéjiā xiǎngxiàng chūlái de. – About 63,000 AU (astronomical units) are equal to one light-year | So according to the scale of light-years | Voyager 1 has just set off | Just left the house | And the perspective position in this photo | At least as far as the radius of the Milky Way | That is, about 50,000 to 90,000 light-years away | That is to say, we have no way to launch a detector | To take a picture of the Milky Way | So the answer can only be | this Photos are imagined by scientists.

虽说是构想图 | 但也是建立在科学的基础之上的 | 那么这张照片是如何构想的呢?Suīshuō shì gòuxiǎng tú | dàn yěshì jiànlì zài kēxué de jīchǔ zhī shàng de | nàme zhè zhāng zhàopiàn shì rúhé gòuxiǎng de ne? – Although it is a conception | but it is also based on science | So how was this photo conceived?

第一就是要遵循宇宙学原理假设 | 也就是我们的宇宙在大尺度上是均匀和各向同性的 | 简而言之 | 我们虽然没有办法给银河系拍一张照片 | 但是我们可以看看其他星系长什么样子 | 这就像是说我知道自己个人 | 但是我不知道自己长什么样子 | 那我总可以看看别人长什么样子吧?Dì yī jiùshì yào zūnxún yǔzhòu xué yuánlǐ jiǎshè | yě jiùshì wǒmen de yǔzhòu zài dà chǐdù shàng shì jūnyún huo gè xiàng tóngxìng de | jiǎn ér yán zhī | wǒmen suīrán méiyǒu bànfǎ gěi yínhéxì pāi yī zhāng zhàopiàn | dànshì wǒmen kěyǐ kàn kàn qítā xīngxì zhǎng shénme yàngzi | zhè jiù xiàng shì shuō wǒ zhīdào zìjǐ gèrén | dànshì wǒ bù zhīdào zìjǐ zhǎng shénme yàngzi | nà wǒ zǒng kěyǐ kàn kàn biérén zhǎng shénme yàngzi ba? – The first is to follow the cosmological principle assumption | that is, our universe is homogeneous and isotropic on a large scale | In short | Although we can’t take a picture of the Milky Way | But we can look at other galaxies What I look like | It’s like saying I know myself | But I don’t know what I look like | Then I can always see what other people look like, right?

哦有鼻子有眼睛 | 这样至少就可以做一个参考 | 比如说天文学家哈勃曾经把 | 星系的形态种类分成了以下几种 | 分别是螺旋星系,椭圆星系,透镜星系和不规则星系等。Ó yǒubíziyǒuyǎn jīng | zhèyàng zhìshǎo jiù kěyǐ zuò yīgè cānkǎo | bǐrú shuō tiānwénxué jiā hā bó céngjīng bǎ | xīngxì de xíngtài zhǒnglèi fēnchéngle yǐxià jǐ zhǒng | fēnbié shì luóxuán xīngxì, tuǒyuán xīngxì, tòujìng xīngxì hé bù guīzé xīngxì děng. – Oh, there are noses and eyes | This can at least be a reference | For example, astronomer Hubble once divided | the morphological types of galaxies into the following types | They are spiral galaxies, elliptical galaxies, lens galaxies, and irregular galaxies.

具体我们看这张图 | 哈勃早期认为星系的发展很有可能是从椭圆星系开始 | 然后演化到中期会变成哈旋星系 | 这里具体又出现了两个分支 | 中间有一个棒状结构的哈旋星系叫做棒旋星系。Jùtǐ wǒmen kàn zhè zhāng tú | hā bó zǎoqí rènwéi xīngxì de fǎ zhǎn hěn yǒu kěnéng shì cóng tuǒyuán xīngxì kāishǐ | ránhòu yǎnhuà dào zhōngqí huì biàn chéng hā xuán xīngxì | zhèlǐ jùtǐ yòu chūxiànle liǎng gè fēnzhī | zhōngjiān yǒu yīgè bàngzhuàng jiégòu de hā xuán xīngxì jiàozuò bàng xuán xīngxì. – Specifically, let’s look at this picture | Hubble believed that the development of galaxies in the early stage was likely to start from elliptical galaxies | Then it would evolve into a spiral galaxy in the middle stage | There are two more branches here | There is a bar-like structure in the middle Spiral galaxies are called barred spiral galaxies.

这就是哈勃认为的一个星系的大致发展走向 | 可是随着人们的观测数据越来越多 | 理论越来越完善 | 现有理论螺旋星系和棒旋星系应该刚好是反过来的 | 螺旋星系和棒旋星系应该是星系的早期结构 | 到了中晚期会演化成随圆星系 | 理由也很简单 | 因为人们发展椭圆星系中主要都是老年恒星 | 而且气体和尘埃的含量都比较少 | 而螺旋星系中的气体尘埃的含量则比较多 | 并且年轻恒星和老年恒星都有 | 所以现在一般认为这个过程是反过来的 | 根据观测数据统计 | 螺旋星系的占比大概在百分之七十七左右 | 百分之二十左右是椭圆星系 | 其余百分之三十一些不规则的星系。

Zhè jiùshì hā bó rènwéi de yīgè xīngxì de dàzhì fāzhǎn zǒuxiàng | kěshì suízhe rénmen de guāncè shùjù yuè lái yuè duō | lǐlùn yuè lái yuè wánshàn | xiàn yǒu lǐlùn luóxuán xīngxì hé bàng xuán xīngxì yīnggāi gānghǎo shì fǎn guòlái de | luóxuán xīngxì hé bàng xuán xīngxì yīnggāi shì xīngxì de zǎoqí jiégòu | dàole zhōng wǎnqí huì yǎnhuà chéng suí yuán xīngxì | lǐyóu yě hěn jiǎndān | yīn wéi rénmen fāzhǎn tuǒyuán xīngxì zhōng zhǔyào dōu shì lǎonián héngxīng | érqiě qìtǐ hé chén’āi de hánliàng dōu bǐjiào shǎo | ér luóxuán xīngxì zhōng de qìtǐ chén’āi de hánliàng zé bǐjiào duō | bìngqiě niánqīng héngxīng hé lǎonián héngxīng dōu yǒu | suǒyǐ xiànzài yībān rènwéi zhège guòchéng shì fǎn guòlái de | gēnjù guāncè shùjù tǒngjì | luóxuán xīngxì de zhàn bǐ dàgài zài bǎi fēn zhī qīshíqī zuǒyòu | bǎi fēn zhī èrshí zuǒyòu shì tuǒyuán xīngxì | qíyú bǎi fēn zhī sānshíyī xiē bù guīzé de xīngxì.

– This is the general development trend of a galaxy according to Hubble | But as people observe more and more data | The theory is getting more and more perfect | The existing theory of spiral galaxies and barred spiral galaxies should be just the opposite | Spiral galaxies and Barred spiral galaxies should be the early structure of galaxies | In the middle and late stages, they will evolve into round galaxies | The reason is very simple | Because people develop elliptical galaxies mainly old stars | And the content of gas and dust is relatively small | And spiral galaxies The content of gas and dust is relatively high | and there are both young and old stars | So now it is generally believed that this process is reversed | According to observational data statistics | The proportion of spiral galaxies is about 77% | About 20 percent are elliptical galaxies | the remaining 30 percent are some irregular galaxies.

这些不规则的星系很可能就是星系碰撞之后形成的样子 | 按照这个比例来看的话 | 我们的宇宙还是很年轻的 | 因为年轻星系居多 | 那么知道了星系的种类 | 我们的银河系应该属于哪一类呢?Zhèxiē bù guīzé de xīngxì hěn kěnéng jiùshì xīngxì pèngzhuàng zhīhòu xíngchéng de yàngzi | ànzhào zhège bǐlì lái kàn dehuà | wǒmen de yǔzhòu háishì hěn niánqīng de | yīnwèi niánqīng xīngxì jūduō | nàme zhīdàole xīngxì de zhǒnglèi | wǒmen de yínhéxì yīnggāi shǔyú nǎ yī lèi ne? – These irregular galaxies are likely to be formed after the collision of galaxies | According to this ratio | Our universe is still very young | Because there are many young galaxies | Then we know the types of galaxies | Which category should our Milky Way belong to? Woolen cloth?

按照比例来说更可能是螺旋系 | 因为比例高 | 而且按照哈勃序列显示 | 我们的银河系的质量符合哈勃序列中的 Sbc 类型 | 也就是一个带有旋臂结构的棒旋星系 | 但是这种猜测是不足以信服人心的 | 所以天文学家又对银河系内的 | 恒星分布进行了一系列的观测 | 二零零五年通过斯皮策空间望运镜 | 首次证实了银河棒的存在 | 也就是证实了我们确实一个棒旋星系 | 那么有几条旋臂呢?

Ànzhào bǐlì lái shuō gèng kěnéng shì luóxuán xì | yīn wéi bǐlì gāo | érqiě ànzhào hā bó xùliè xiǎnshì | wǒmen de yínhéxì de zhìliàng fúhé hā bó xùliè zhōng de Sbc lèixíng | yě jiùshì yīgè dài yǒu xuán bì jiégòu de bàng xuán xīngxì | dànshì zhè zhǒng cāicè shì bùzú yǐ xìnfú rénxīn de | suǒyǐ tiānwénxué jiā yòu duì yínhéxì nèi de | héngxīng fēnbù jìnxíngle yī xìliè de guāncè | èr líng líng wǔ nián tōngguò sī pí cè kōngjiān wàng yùn jìng | shǒucì zhèngshíle yínhé bàng de cúnzài | yě jiùshì zhèngshíle wǒmen quèshí yīgè bàng xuán xīngxì | nàme yǒu jǐ tiáo xuán bì ne?

– It is more likely to be a spiral system proportionally | because the ratio is high | and according to the Hubble sequence | the mass of our Milky Way corresponds to the Sbc type in the Hubble sequence | that is, a barred spiral galaxy with a spiral arm structure | but this This kind of speculation is not convincing | So astronomers made a series of observations on the | stellar distribution in the Milky Way | Spitzer Space Telescope in 2005 | The existence of the Milky Way bar was confirmed for the first time | It just confirms that we are indeed a barred spiral galaxy | How many spiral arms are there?

通过追踪电离氢和分子云的密度 | 显示银河系的旋臂主要有四条 | 还有一些不完整的分支或者说小臂 | 这四条主要壁包括:英仙座旋臂,人马座旋臂,天鹅尺旋臂和质牌-南十字旋臂 | 次要旋臂就包括我们所在的猎户臂 | 然而我们是否真的在猎户臂上 | 这件事儿也是存在争议的 | 可见银河系的尺度有多大 | 所以对于银河系具体结构的定论目前还是没有的 | 前几年主要旋臂还认为有两条呢?Tōngguò zhuīzōng diànlí qīng hé fēnzǐ yún de mìdù | xiǎnshì yínhéxì de xuán bì zhǔyào yǒu sìtiáo | hái yǒu yīxiē bù wánzhěng de fēnzhī huòzhě shuō xiǎo bì | zhè sìtiáo zhǔyào bì bāokuò: Yīng xiān zuò xuán bì, rénmǎzuò xuán bì, tiān’é chǐ xuán bì hé zhì pái-nán shízì xuán bì | cì yào xuán bì jiù bāokuò wǒmen suǒzài de lièhù bì | rán’ér wǒmen shìfǒu zhēn de zài lièhù bì shàng | zhè jiàn shì er yěshì cúnzài zhēngyì de | kějiàn yínhéxì de chǐdù yǒu duōdà | suǒyǐ duìyú yínhéxì jùtǐ jiégòu de dìnglùn mùqián háishì méiyǒu de | qián jǐ nián zhǔyào xuán bì hái rènwéi yǒu liǎng tiáo ne? – By tracking the density of ionized hydrogen and molecular clouds | It shows that there are four main spiral arms of the Milky Way | There are also some incomplete branches or small arms | The four main walls include: Perseus spiral arm, Sagittarius spiral arm, Cygnus ruler spiral Arms and Quality Cards – Southern Cross Arm | The secondary arm includes the Orion Arm where we are | However, whether we are really on the Orion Arm | This matter is also controversial | It can be seen how big the Milky Way is | So for There is still no conclusion on the specific structure of the Milky Way | In the past few years, do you think there are two main spiral arms?

现在变成四条了 | 综上所述 | 大家经常看到的这张银河系全景图片 | 就是根据现有的观测数据 | 通过计算机模拟出来的 | 不过我相信这张图片一定会越来越完善 | 随着 EHT(事件视界望远镜) 拍摄到了银心黑洞的照片 | 也让我们对于银河系的内部结构有了更深层次的了解 | 比如说这张照片是斯皮策望远镜对着银心方向拍摄的一张照片 | 其中密密麻的亮点都是恒星 | 红色的部分是宇宙尘埃 | 而最中心的那个最亮的点 | 就是银心的人马座 A* 黑洞 | 如今我们已经把这张照片放大了无数倍 | 直接看到了人马座 A* 的样子 | 所以未来 | 我们对于银河系对于宇宙 | 一定会了解的越来越透彻,清晰 | 好吧今天的视频到这 | 我是妈咪叔一个较真儿的理工男 | 咱们不期见拜拜。

Xiànzài biàn chéng sìtiáole | zòng shàng suǒ shù | dàjiā jīngcháng kàn dào de zhè zhāng yínhéxì quánjǐng túpiàn | jiùshì gēnjù xiàn yǒu de guāncè shùjù | tōngguò jìsuànjī mónǐ chūlái de | bùguò wǒ xiāngxìn zhè zhāng túpiàn yīdìng huì yuè lái yuè wánshàn | suízhe EHT(shìjiàn shìjiè wàngyuǎnjìng) pāishè dàole yín xīn hēidòng de zhàopiàn | yě ràng wǒmen duìyú yínhéxì de nèibù jiégòu yǒule gēngshēn céngcì de liǎojiě | bǐrú shuō zhè zhāng zhàopiàn shì sī pí cè wàngyuǎnjìng duìzhe yín xīn fāngxiàng pāishè de yī zhāng zhàopiàn | qízhōng mì mi má de liàngdiǎn dōu shì héngxīng | hóngsè de bùfèn shì yǔzhòu chén’āi | ér zuì zhōngxīn dì nàgè zuì liàng de diǎn | jiùshì yín xīn de rénmǎzuò A* hēidòng | rújīn wǒmen yǐjīng bǎ zhè zhāng zhàopiàn fàng dà liǎo wúshù bèi | zhíjiē kàn dàole rénmǎzuò A* de yàngzi | suǒyǐ wèilái | wǒmen duìyú yínhéxì duìyú yǔzhòu | yīdìng huì liǎojiě de yuè lái yuè tòuchè, qīngxī | hǎo ba jīntiān de shìpín dào zhè | wǒ shì mā mī shū yīgè jiàozhēn er de lǐgōng nán | zánmen bù qī jiàn bàibài.

– Now it has become four | To sum up the above | This panoramic picture of the Milky Way that everyone often sees | is based on existing observation data | The EHT (Event Horizon Telescope) took a picture of the galactic center black hole | It also gave us a deeper understanding of the internal structure of the Milky Way | For example, this photo is a picture taken by the Spitzer telescope in the direction of the galactic center | The dense bright spots are all stars| The red part is cosmic dust| And the brightest point in the center| is the black hole of Sagittarius A* in the center of the Milky Way| Now we have magnified this photo countless times| Direct I saw the appearance of Sagittarius A* | So in the future | We will know more and more about the Milky Way and the universe | See you bye.

https://www.youtube.com/embed/4PW_8JLXXJQ?start=00

如何测定基本电荷量?密立根油滴实验为什么被别人当做反面教材?

Rúhé cèdìng jīběn diànhè liàng? Mì lìgēn yóu dī shíyàn wèishéme bèi biérén dàngzuò fǎnmiàn jiàocái?

How to determine the basic charge? Why is the Millikan Oil Drop Experiment used as a negative textbook by others?

https://youglish.com/pronounce/%E6%98%BE%E5%BE%AE%E9%95%9C/chinese?

https://www.youtube.com/embed/PaLK7PFCeC4?start=00

妈咪说 知识就是力量 大家好 我是妈咪叔

今天终于咱们要讲这个系列最后一期视频了

就是最美物理实验第三名:密立根油滴实验

第二名伽利略的自由落体和第一名电子干涉实验咱们之前都说过了

油滴实验怎么说呢

可能是这份名单里争议最大的了

Mā mī shuō zhīshì jiùshì lìliàng dàjiā hǎo wǒ shì mā mī shū jīntiān zhōngyú zánmen yào jiǎng zhège xìliè zuìhòu yī qí shìpínle jiùshì zuìměi wùlǐ shíyàn dì sān míng: Mì lìgēn yóu dī shíyàn dì èr míng jiālìlüè de zìyóu luòtǐ hé dì yī míng diànzǐ gānshè shíyàn zánmen zhīqián dōu shuōguòle yóu dī shíyàn zěnme shuō ne kěnéng shì zhè fèn míngdān lǐ zhēngyì zuìdà dele

Mommy said that knowledge is power. Hello, everyone. I’m Uncle Mommy.

Today we are finally going to talk about the last video of this series

It is the third place in the most beautiful physics experiment: Millikan oil drop experiment

We’ve talked about the second place Galileo’s free fall and the first place electron interference experiment.

What do you say about the oil drop experiment?

Probably the most controversial in this list

它的意义是挺美的

不过实验确实不怎么美啊

尤其本科的同学做过你就知道了

盯着显微镜或者CCD看一下午

结果是误差大于百分之二十还整满手油

Tā de yìyì shì tǐng měide bùguò shíyàn quèshí bù zě me měi a yóuqí běnkē de tóngxué zuòguò nǐ jiù zhīdàole dīngzhe xiǎnwéijìng huòzhě CCD kàn yī xiàwǔ jiéguǒ shì wùchā dàyú bǎi fēn zhī èrshí hái zhěng mǎn shǒu yóu

Its meaning is quite beautiful

But the experiment is really not so beautiful

Especially undergraduate students who have done it, you will know

Stare at the microscope or CCD all afternoon

The result is that the error is greater than 20% and it’s full of oil

最终就是大部分人都是昧着良心改数据过的 没说错吧

来吧 进入正题

密立根 美国物理学家 一九二三年诺贝尔物理学奖得主

咱们在粒子专辑已经介绍不少他的故事了

那直接看实验

Zuìzhōng jiùshì dà bùfèn rén dōu shì mèizhe liángxīn gǎi shùjùguò de méi shuō cuò ba lái ba jìnrù zhèngtí mì lìgēn měiguó wùlǐ xué jiā yījiǔ’èrsān nián nuò bèi’ěr wùlǐ xué jiǎng dézhǔ zánmen zài lìzǐ zhuānjí yǐjīng jièshào bù shǎo tā de gùshìle nà zhíjiē kàn shíyàn

In the end, most people have changed their data ignorantly, right?

Come on, go to the topic

Millikan, American physicist, winner of the Nobel Prize in Physics in 1923

We have already introduced a lot of his stories in the particle album

Then just look at the experiment

油滴实验在当年主要为了解决一个什么问题呢

就是电荷有没有基本单位

那自然有人认为是没有的无下限

还有人认为电荷的基本单位都不是一个固定值

它是随着条件而变化的

这个时候密立根就发挥聪明才智了

说别争了 做个实验测一下不就知道了嘛

Yóu dī shíyàn zài dāngnián zhǔyào wèi liǎo jiějué yīgè shénme wèntí ne jiùshì diànhè yǒu méiyǒu jīběn dānwèi nà zìrán yǒurén rènwéi shì méiyǒu de wú xiàxiàn hái yǒurén rènwéi diànhè de jīběn dānwèi dōu bùshì yīgè gùdìng zhí tā shì suízhe tiáojiàn ér biànhuà de zhège shíhòu mì lìgēn jiù fāhuī cōngmíng cáizhìle shuō bié zhēngle zuò gè shíyàn cè yīxià bù jiù zhīdàole ma

What problem was the main purpose of the oil drop experiment to solve that year?

Is there a basic unit of charge?

Naturally some people think that there is no lower limit

Some people think that the basic unit of charge is not a fixed value

It changes with conditions

Millikan was using his ingenuity at this time

Say don’t fight, don’t you know if you do an experiment

怎么做呢 油滴实验的基本思想先和大家说一下

很简单 就是我测量很多个油滴它们所带的电荷量

然后我看这一堆数据能不能同时被一个更小的数整除

也就是找到一个公因数

如果能找到这个数就说明电荷有基本单位

能明白吧?是不是很简单?

那问题就来了 我怎么测量一个小油滴的电荷呢?

Zěnme zuò ne yóu dī shíyàn de jīběn sīxiǎng xiān hé dàjiā shuō yīxià hěn jiǎndān jiùshì wǒ cèliáng hěnduō gè yóu dī tāmen suǒ dài de diànhè liàng ránhòu wǒ kàn zhè yī duī shùjù néng bùnéng tóngshí bèi yīgè gèng xiǎo de shù zhěngchú yě jiùshì zhǎodào yīgè gōng yīnshù rúguǒ néng zhǎodào zhège shù jiù shuōmíng diànhè yǒu jīběn dānwèi néng míngbái ba? Shì bùshì hěn jiǎndān? Nà wèntí jiù láile wǒ zěnme cèliáng yīgè xiǎo yóu dī de diànhè ne?

How to do it, let me talk about the basic idea of the oil drop experiment first

It’s very simple. I measure the electric charge of many oil droplets.

Then I see if this bunch of data can be divisible by a smaller number at the same time

Is to find a common factor

If you can find this number, it means that the charge has a basic unit

Can you understand? Is not it simple?

So the question is how do I measure the charge of a small oil droplet?

密立根的主要贡献就在这了

一九零九年 密立根设计了一套仪器就可以解决这个问题

下面咱们就来看看他是怎么做的

注意和你们在实验室做的不太一样啊

毕竟当年没有那么先进

首先需要准备一个喷嘴

其实这个喷嘴就是当时喷香水用的

可以把液体以小液滴的形式喷出来

然后里面装上油 为什么不用水呢?

Mì lìgēn de zhǔyào gòngxiàn jiù zài zhèle yījiǔ líng jiǔ nián mì lìgēn shèjìle yī tào yíqì jiù kěyǐ jiějué zhège wèntí xiàmiàn zánmen jiù lái kàn kàn tā shì zěnme zuò de zhùyì hé nǐmen zài shíyàn shì zuò de bù tài yīyàng a bìjìng dāngnián méiyǒu nàme xiānjìn shǒuxiān xūyào zhǔnbèi yīgè pēnzuǐ qíshí zhège pēnzuǐ jiùshì dāngshí pèn xiāngshuǐ yòng de kěyǐ bǎ yètǐ yǐ xiǎo yè dī de xíngshì pēn chūlái ránhòu lǐmiàn zhuāng shàng yóu wèishéme bùyòng shuǐ ne?

Millikan’s main contribution is here

In 1909, Millikan designed a set of instruments to solve this problem.

Let’s take a look at how he did it

Note that it is different from what you did in the laboratory

After all, it was not so advanced back then

First you need to prepare a nozzle

Actually this nozzle was used to spray perfume at the time

Can spray liquid in the form of small droplets

Then it’s filled with oil, why not use water?

因为水太容易蒸发了

所以选择了蒸气压比较低的油

然后用两块金属板水平方式平行排列做一个均匀电场

然后施加一个电位差

当时最高可以施加五千三百伏的电压

上面是负极 下面是正电极

在负电极板上开几个小孔

为了让部分油滴可以飘进来

在侧面放置一个显微镜来观察

没了 这就基本上是当时的全部道具

先就是捏一下喷嘴 让一部分油滴飘进来

Yīn wéi shuǐ tài róngyì zhēngfāle suǒyǐ xuǎnzéle zhēngqì yā bǐjiào dī de yóu ránhòu yòng liǎng kuài jīnshǔ bǎn shuǐpíng fāngshì píng háng páiliè zuò yīgè jūnyún diànchǎng ránhòu shījiā yīgè diànwèi chā dāngshí zuìgāo kěyǐ shījiā wǔqiān sānbǎi fú de diànyā shàngmiàn shì fùjí xiàmiàn shìzhèng diànjí zài fù diànjí bǎn shàng kāi jǐ gè xiǎo kǒng wèile ràng bùfèn yóu dī kěyǐ piāo jìnlái zài cèmiàn fàngzhì yīgè xiǎnwéijìng lái guānchá méiliǎo zhè jiù jīběn shàng shì dāngshí de quánbù dàojù xiān jiùshì niē yīxià pēnzuǐ ràng yībùfèn yóu dī piāo jìnlái

Because the water evaporates too easily

So I chose oil with lower vapor pressure

Then two metal plates are arranged in parallel in a horizontal manner to create a uniform electric field

Then apply a potential difference

At that time, a maximum voltage of 5,300 volts could be applied

The top is the negative electrode, and the bottom is the positive electrode

Make a few small holes in the negative electrode plate

In order to allow some oil droplets to float in

Place a microscope on the side to observe

No, this is basically all the props at the time

First, squeeze the nozzle to let some oil droplets float in

然后受到重力的影响自然下落

可是我们要测量的是油滴所带的电荷啊?

怎们让这些油滴带上微弱的电荷呢?

其实现在的实验什么都不用做

因为油滴从喷嘴喷出的时候就会有一部分通过和喷嘴的摩擦已经带电了

摩擦起电嘛

而且每次实验只要有少数油滴带电就可以了

然后从这里面再选一个做实验对象

Ránhòu shòudào zhònglì de yǐngxiǎng zìrán xiàluò kěshì wǒmen yào cèliáng de shì yóu dī suǒ dài de diànhè a? Zěnmen ràng zhèxiē yóu dī dài shàng wéiruò de diànhè ne? Qíshí xiànzài de shíyàn shénme dōu bùyòng zuò yīnwèi yóu dī cóng pēnzuǐ pēn chū de shíhòu jiù huì yǒu yībùfèn tōngguò hé pēnzuǐ de mócā yǐjīng dàidiànle mócā qǐ diàn ma érqiě měi cì shíyàn zhǐyào yǒu shǎoshù yóu dī dàidiàn jiù kěyǐle ránhòu cóng zhè lǐmiàn zài xuǎn yīgè zuò shíyàn duìxiàng

Then fall naturally under the influence of gravity

But what we want to measure is the electric charge carried by the oil droplets?

How can we make these oil droplets carry a weak charge?

Actually, you don’t need to do anything in the experiment now

Because when the oil droplets are ejected from the nozzle, part of the friction with the nozzle will be charged.

Friction electrification

And only a few oil droplets are charged in each experiment.

Then choose another one to be the test subject

这样数据好统计 不容易乱

然后重复多次实验

但是当时应该是为了严谨 以防万一

密立根是这么做的

它在上部的空气中射入一束X射线

这束X射线就会电离一部分空气

就是剥夺了空气分子的电子

然后这个离子化的空气分子和油滴接触之后

就会把正电荷转移到油滴上 这样油滴就带电了

怎们着都成 只要它带电咱们就有数据

好 现在假设某一个带电的油滴正在下落

Zhèyàng shùjù hǎo tǒngjì bù róngyì luàn ránhòu chóngfù duō cì shíyàn dànshì dāngshí yīnggāi shì wèile yánjǐn yǐ fáng wàn yī mì lìgēn shì zhème zuò de tā zài shàngbù de kōngqì zhòng shè rù yī shù X shèxiàn zhè shù X shèxiàn jiù huì diànlí yībùfèn kōngqì jiùshì bōduóle kōngqì fēnzǐ de diànzǐ ránhòu zhège lízǐ huà de kōngqì fēnzǐ hé yóu dī jiēchù zhīhòu jiù huì bǎ zhèng diànhè zhuǎnyí dào yóu dī shàng zhèyàng yóu dī jiù dàidiànle zěnmenzhe dōu chéng zhǐyào tā dàidiàn zánmen jiù yǒu shùjù hǎo xiànzài jiǎshè mǒu yīgè dàidiàn de yóu dī zhèngzài xiàluò

This way the data is good for statistics and not easy to mess up

Then repeat the experiment many times

But it should be for rigor, just in case

Millikan did this

It shoots a beam of X-rays in the upper air

This X-ray ionizes part of the air

Is to deprive the air molecules of electrons

Then after the ionized air molecules come into contact with the oil droplets

Will transfer the positive charge to the oil droplets so that the oil droplets are charged.

No matter what happens, as long as it is powered on, we have data

Ok, now suppose a certain charged oil drop is falling

它会受到哪些力呢?受力分析

首先重力mg肯定有了

然后空气阻力 可以通过斯托克斯定律求出来

没学过流体力学的同学没关系

你肯定知道有空气阻力对吧

如果打开电源还会受到一个电场力

现在假设在不打开电场的情况下

油滴下落的状态大致是这样的

先是加速运动 达到一定速度改匀速了

说明什么啊?

Tā huì shòudào nǎxiē lì ne? Shòu lì fēnxī shǒuxiān zhònglì mg kěndìng yǒule ránhòu kōngqì zǔlì kěyǐ tōngguò sī tuō kè sī dìnglǜ qiú chūlái méi xuéguò liútǐ lìxué de tóngxué méiguānxì nǐ kěndìng zhīdào yǒu kòng qì zǔlì duì ba rúguǒ dǎkāi diànyuán hái huì shòudào yīgè diànchǎng lì xiànzài jiǎshè zài bù dǎkāi diànchǎng de qíngkuàng xià yóu dī xiàluò de zhuàngtài dàzhì shì zhèyàng de xiānshi jiāsù yùndòng dádào yīdìng sùdù gǎi yúnsùle shuōmíng shénme a?

What forces will it receive? Force analysis

First of all, there must be gravity mg

Then the air resistance can be calculated by Stokes’ law

It’s okay for students who haven’t studied fluid mechanics

You must know that there is air resistance, right

If you turn on the power, you will receive an electric field force

Now suppose that without turning on the electric field

The state of the oil drop is roughly like this

First, accelerate the movement and reach a certain speed to change to a uniform speed.

What does it mean?

说明重力和阻力相等了

匀速运动合外力为零嘛

但是各位注意 为了严谨

其实咱们还有一个力没有考虑 什么啊?

浮力 油滴是会受到空气的一个浮力的

这个力最容易被忽略

浮力定律ρ液gV排

最经典的一个例子咱们之前说过

一吨铁和一吨木头那个重啊?

你要问质量肯定是相等的

但是要问哪个重 问重量

在空气中称是一吨铁更重

因为木头体积大 受到的浮力更大 明白吧?

Shuōmíng zhònglì hé zǔlì xiāngděngle yúnsù yùndòng hé wàilì wéi líng ma dànshì gèwèi zhùyì wèile yánjǐn qíshí zánmen hái yǒu yīgè lì méiyǒu kǎolǜ shénme a? Fúlì yóu dī shì huì shòudào kōngqì de yīgè fúlì de zhège lì zuì róngyì bèi hūlüè fúlì dìnglǜ r yè gV pái zuì jīngdiǎn de yīgè lìzi zánmen zhīqián shuōguò yī dūn tiě hé yī dūn mùtou nàgè zhòng a? Nǐ yào wèn zhìliàng kěndìng shì xiāngděng de dànshì yào wèn nǎge zhòng wèn zhòngliàng zài kōngqì zhòng chēng shì yī dūn tiě gèng zhòng yīnwèi mùtou tǐjī dà shòudào de fúlì gēng dà míngbái ba?

It shows that gravity and resistance are equal

Is the external force of uniform motion zero?

But please pay attention, for rigor

Actually, we still have one power that we haven’t considered.

Buoyancy Oil droplets are subject to a buoyancy force from the air

This force is most easily overlooked

The law of buoyancy ρ liquid gV row

The most classic example we have said before

How heavy is a ton of iron and a ton of wood?

You have to ask that the quality must be equal

But which weight to ask, ask weight

In the air, a ton of iron is heavier

Because the wood is larger, the buoyancy is greater, understand?

所以油滴匀速运动的时候的受力分析就应该是阻力=重力-浮力

应该这么列方程

我还是写出来给大家看吧

先观测某一个油滴自然下落到匀速 记录这个速度为v

然后根据刚才的受力分析阻力F=重力W-浮力B

阻力F根据斯托克斯定律=6πrηv

其中η叫做粘滞系数 就是粘度

一般常温下空气的粘度是一个常数

大概是1.81*10^-5Pa·s

Suǒyǐ yóu dī yúnsù yùndòng de shíhòu de shòu lì fēnxī jiù yīnggāi shì zǔlì =zhònglì-fúlì yīnggāi zhème liè fāngchéng wǒ háishì xiě chūlái gěi dàjiā kàn ba xiān guāncè mǒu yīgè yóu dī zìrán xiàluò dào yúnsù jìlù zhège sùdù wèi v ránhòu gēnjù gāngcái de shòu lì fēnxī zǔlì F=zhònglì W-fúlì B zǔlì F gēnjù sī tuō kè sī dìnglǜ =6prēv qízhōng ē jiàozuò zhān zhì xìshù jiùshì niándù yībān chángwēn xià kōngqì de niándù shì yīgè chángshù dàgài shì 1.81*10^-5Pa·s

Therefore, when the oil droplet is moving at a constant speed, the force analysis should be resistance = gravity-buoyancy

Should be such a list of equations

I’ll write it down for everyone to see

First observe that an oil droplet naturally falls to a constant speed, and record this speed as v

Then according to the force analysis just now, the resistance F=gravity W-buoyancy B

Resistance F according to Stokes’ law = 6πrηv

Where η is called the viscosity coefficient, which is the viscosity

Generally, the viscosity of air at room temperature is a constant

Probably 1.81*10^-5Pa·s

你知道就行

r就是油滴的半径

因为受到表面张力的影响

油滴几乎就是一个正球体了

重力W=mg

浮力B=ρ液gV排=4/3πr^3ρ空g

那我们把这些公式带进去之后就可以求出这个油滴的半径r

半径r求出来之后带入这三个公式就可求出每一个力的大小了

下一步要做的就是通过电场来控制油滴

让这个下落的油滴保持在空气中静止

这样我们就又得到一个受力分析方程

静止了就没有阻力了对吧

所以就是电场力Fe=重力W-浮力B

电场力等于什么啊?

Nǐ zhīdào jiùxíng r jiùshì yóu dī de bànjìng yīnwèi shòudào biǎomiàn zhānglì de yǐngxiǎng yóu dī jīhū jiùshì yīgè zhèng qiútǐle zhònglì W=mg fúlì B=r yè gV pái =4/3pr^3r kōng g nà wǒmen bǎ zhèxiē gōngshì dài jìnqù zhīhòu jiù kěyǐ qiú chū zhège yóu dī de bànjìng r bànjìng r qiú chūlái zhīhòu dài rù zhè sān gè gōngshì jiù kě qiú chū měi yīgè lì de dàxiǎole xià yībù yào zuò de jiùshì tōngguò diànchǎng lái kòngzhì yóu dī ràng zhège xiàluò de yóu dī bǎochí zài kōngqì zhòng jìngzhǐ zhèyàng wǒmen jiù yòu dédào yīgè shòu lì fēnxī fāngchéng jìngzhǐle jiù méiyǒu zǔlìle duì ba suǒyǐ jiùshì diànchǎng lì Fe=zhònglì W-fúlì B diànchǎng lì děngyú shénme a?

You know it

r is the radius of the oil drop

Because of the influence of surface tension

The oil drop is almost a true sphere

Gravity W=mg

Buoyancy B=ρ liquid gV row=4/3πr^3ρ empty g

Then we can find the radius r of this oil drop after we take these formulas in

After the radius r is calculated, the three formulas can be used to calculate the magnitude of each force.

The next step is to control the oil droplets through the electric field

Keep this falling oil drop still in the air

In this way, we get another force analysis equation

There is no resistance when it is still, right

So the electric field force Fe=gravity W-buoyancy B

What is the electric field force?

电场力=电荷*电场

平行板的电场E=电位差V/平行板的距离d

所以再把这几个式子联立

我们就可以求出油滴所带电荷的公式了

q=4πr^3g(ρ-ρ空)d/3V

这样一个油滴所带的电荷量咱们就求出来了

然后重复实验测量多个油滴的电荷量

找出公因数 就得到基本电荷量了

当时密立根公布自己做了58个实验数据

最终找到的基本电荷量是4.774*10^-10静库伦

如果换算成国际单位制就是1.5924*10^-19库伦

最新的基本电荷量是1.602176634*10^-19库伦

密立根得到的结果误差小于1%

后人经过分析这个误差也找到原因了

主要就是因为在空气的粘滞系数的选取上

因为在油滴太小

小到和空气粒子差距不大的时候

斯托克斯定律就不适用了

所以空气的粘滞系数必须要修正一下

但是当时也不知道 误差就出在这了

以上就是密立根油滴实验

看起来好像挺复杂但是原理还是很简单的

就几个公式就OK了

但是为什么说这个实验有争议呢?

Diànchǎng lì =diànhè*diànchǎng píngxíng bǎn de diànchǎng E=diànwèi chā V/píngxíng bǎn de jùlí d suǒyǐ zài bǎ zhè jǐ gè shì zi lián lì wǒmen jiù kěyǐ qiú chū yóu dī suǒ dài diànhè de gōngshìle q=4pr^3g(r-r kōng)d/3V zhèyàng yīgè yóu dī suǒ dài de diànhè liàng zánmen jiù qiú chūláile ránhòu chóngfù shíyàn cèliáng duō gè yóu dī de diànhè liàng zhǎo chū gōng yīnshù jiù dédào jīběn diànhè liàngle dāngshí mì lìgēn gōngbù zìjǐ zuòle 58 gè shíyàn shùjù zuìzhōng zhǎodào de jīběn diànhè liàng shì 4.774*10^-10 Jìng kùlún rúguǒ huànsuàn chéng guójì dānwèi zhì jiùshì 1.5924*10^-19 Kùlún zuìxīn de jīběn diànhè liàng shì 1.602176634*10^-19 Kùlún mì lìgēn dédào de jiéguǒ wùchā xiǎoyú 1% hòu rén jīngguò fèn xī zhège wùchā yě zhǎodào yuányīnle zhǔyào jiùshì yīnwèi zài kōngqì de zhān zhì xì shǔ de xuǎnqǔ shàng yīnwèi zài yóu dī tài xiǎo xiǎo dào hé kōngqì lìzǐ chājù bù dà de shíhòu sī tuō kè sī dìnglǜ jiù bù shìyòngle suǒyǐ kōngqì de zhān zhì xìshù bìxū yào xiūzhèng yīxià dànshì dāngshí yě bù zhīdào wùchā jiù chū zài zhèle yǐshàng jiùshì mì lìgēn yóu dī shíyàn kàn qǐlái hǎoxiàng tǐng fùzá dànshì yuánlǐ háishì hěn jiǎndān de jiù jǐ gè gōngshì jiù OKle dànshì wèishéme shuō zhège shíyàn yǒu zhēngyì ne?

Electric field force = charge * electric field

The electric field of the parallel plate E=potential difference V/the distance d of the parallel plate

So combine these formulas

We can find the formula for the electric charge of the oil droplets

q=4πr^3g(ρ-ρempty)d/3V

We can figure out the amount of electric charge carried by such an oil drop

Then repeat the experiment to measure the electric charge of multiple oil droplets

Find out the common factor and get the basic charge

At that time Millikan announced that he had done 58 experimental data

The basic charge finally found is 4.774*10^-10 static coulomb

If converted to the International System of Units, it is 1.5924*10^-19 Coulomb

The latest basic charge is 1.602176634*10^-19 Coulomb

The results obtained by Millikan have an error of less than 1%

Later generations found the reason for this error after analyzing

Mainly because of the selection of the viscosity coefficient of air

Because the oil droplets are too small

When it’s so small that it’s not too far from the air particles,

Stokes’ law does not apply

So the viscosity coefficient of air must be corrected

But I didn’t know at the time. The error was here.

The above is the Millikan oil drop experiment

It looks complicated but the principle is still very simple

Just a few formulas are OK

But why is this experiment controversial?

甚至被好多人拿过来当反面教材

就是因为后来史学家考证

实际上密立根当时做了140组实验

就是手里有140个实验结果

但是他从中选取了58个结果作为最终结论

我们知道 做实验最怕的就是这个

主观臆断是最不符合客观事实的

只要不是人为因素 多大的误差都要接受

所以密立根删除了自己感觉误差比较大的结果

这件事就被很多人拿过来说事

说的最狠的可能就是费曼

当然费曼不是主要针对密立根

他说的是科研精神

就是说密立根当年得出的实验结果不是比真实值小嘛

费曼说如果你把从密立根之后的人做的实验结果拿出来

再整理一下的话你就会发现一个有趣的事儿

就是每次人们做的实验结果都是比密立根的大那么一丢丢

不是直接就高到正确数值那去了

为啥啊?就是因为每个人考虑的都是

人家密立根都因为这个实验得诺奖了

所以误差肯定不会太大的

即使自己得到了一个正确的结果

一看和密立根的差太多 就赶紧修正一下

不能差太多 一定是我错了

费曼也直言 这是让很多科学家惭愧脸红的事

其实说到底就是妈咪叔总说的较真儿

要有科研精神 科学一定要客观

还有一个事儿也总被别人拿来说事

就是当年密立根这个实验实际上是和他的一名研究生一起做的

但是最终的论文只有密立根一个人的署名

而且你知道的 说是导师和研究生一起做实验

Shènzhì bèi hǎoduō rén ná guòlái dāng fǎnmiàn jiàocái jiùshì yīnwèi hòulái shǐxué jiā kǎozhèng shíjì shang mì lìgēn dāngshí zuòle 140 zǔ shíyàn jiùshì shǒu li yǒu 140 gè shíyàn jiéguǒ dànshì tā cóng zhòng xuǎnqǔle 58 gè jiéguǒ zuòwéi zuìzhōng jiélùn wǒmen zhīdào zuò shíyàn zuì pà de jiùshì zhège zhǔguān yìduàn shì zuì bù fúhé kèguān shìshí de zhǐyào bùshì rénwéi yīnsù duōdà de wùchā dōu yào jiēshòu suǒyǐ mì lìgēn shānchúle zìjǐ gǎnjué wùchā bǐjiào dà de jiéguǒ zhè jiàn shì jiù bèi hěnduō rén ná guòlái shuō shì shuō de zuì hěn de kěnéng jiùshì fèi màn dāngrán fèi màn bùshì zhǔyào zhēnduì mì lìgēn tā shuō de shì kēyán jīngshén jiùshì shuō mì lìgēn dāngnián dé chū de shíyàn jiéguǒ bùshì bǐ zhēnshí zhí xiǎo ma fèi màn shuō rúguǒ nǐ bǎ cóng mì lìgēn zhīhòu de rén zuò de shíyàn jiéguǒ ná chūlái zài zhěnglǐ yīxià dehuà nǐ jiù huì fāxiàn yīgè yǒuqù de shì er jiùshì měi cì rénmen zuò de shíyàn jiéguǒ dōu shì bǐ mì lìgēn de dà nàme yī diū diū bùshì zhíjiē jiù gāo dào zhèngquè shùzhí nà qùle wèi shà a? Jiùshì yīnwèi měi gèrén kǎolǜ de dōu shì rénjiā mì lìgēn dōu yīnwèi zhège shíyàn dé nuò jiǎngle suǒyǐ wùchā kěndìng bù huì tài dà de jíshǐ zìjǐ dédàole yīgè zhèngquè de jiéguǒ yī kàn hé mì lìgēn de chà tài duō jiù gǎnjǐn xiūzhèng yīxià bùnéng chà tài duō yīdìng shì wǒ cuòle fèi màn yě zhíyán zhè shì ràng hěnduō kēxuéjiā cánkuì liǎnhóng de shì qíshí shuō dàodǐ jiùshì mā mī shū zǒng shuō de jiàozhēn er yào yǒu kēyán jīngshén kēxué yīdìng yào kèguān hái yǒu yīgè shì er yě zǒng bèi biérén ná lái shuō shì jiùshì dāngnián mì lìgēn zhège shíyàn shíjì shang shì hé tā de yī míng yánjiūshēng yīqǐ zuò de dànshì zuìzhōng dì lùnwén zhǐyǒu mì lìgēn yīgè rén de shǔmíng érqiě nǐ zhīdào de shuō shì dǎoshī hé yánjiūshēng yīqǐ zuò shíyàn

It was even taken over by many people as negative teaching materials

Because later historians verified

In fact, Millikan did 140 experiments

It means there are 140 experimental results in hand

But he selected 58 results as the final conclusion

We know that this is what we are most afraid of doing experiments

Subjective assumptions are the most inconsistent with objective facts

As long as it is not human factors, big errors must be accepted

So Millikan deleted the result that he felt was relatively large

This incident has been taken by many people to talk about it

The most ruthless one might be Feynman

Of course Feynman is not mainly targeting Millikan

He is talking about the spirit of scientific research

That is to say, the experimental results obtained by Millikan back then are less than the true value.

Feynman said that if you take out the results of experiments done by people after Millikan,

If you sort it out a bit, you will find an interesting thing

It means that every time people do experiments, the results are so much bigger than Millikan’s.

It’s not just as high as the correct value.

why? Because everyone thinks about

Millikan won the Nobel Prize for this experiment

So the error will not be too big

Even if I got a correct result

Seeing that there is too much difference between Millikan and Millikan, I quickly corrected it.

I can’t be too bad, I must be wrong

Feynman also bluntly said that this is something that makes many scientists ashamed and blushing.

In fact, uncle Mommy always said it was more truthful

Must have scientific research spirit, science must be objective

There is one more thing that is always cited by others

Millikan’s experiment was actually done with one of his graduate students.

But the final paper was signed by Millikan alone

And you know, it’s the tutor and the graduate student doing experiments together

实际上导师基本上就是提出课题

然后瞻前马后做实验记录数据全都是研究生的活

导师才不管那事儿呢

所以不给人家一个名分确实不应该

那今天咱们就算是为这位前辈正个名

当年油滴实验的真实操作者这位密立根的研究生叫做

哈维·弗莱彻Fletcher 美国物理学家

其实他之后的贡献更多

他之后一直从事和声学有关的研究

曾经在贝尔实验室工作

他发明了一个2-A听力计

就是也算是早期研究电子助听器的人了

他应该还是第一个发明了现代立体声录音的人

现存最早的立体声录音就是有Fletcher团队完成录制的

你像我们现在随随便便都能听到立体声

要感谢这位Fletcher

因此他也被人们称作立体声之父

这是美国声学学会继爱迪生之后的第二个荣誉会员

在2016年Fletcher还获得格莱美奖 当然是已故奖

就是为了纪念他老人家在音乐立体声录制方面的贡献

也是一位传奇人物是吧

好 今天就唠到这

我是妈咪叔 一个较真儿的理工男

下期见 拜拜

Shíjì shang dǎoshī jīběn shàng jiùshì tíchū kètí ránhòu zhān qián mǎ hòu zuò shíyàn jìlù shùjù quándōu shì yánjiūshēng de huó dǎoshī cái bùguǎn nà shì er ne suǒyǐ bù jǐ rénjiā yì gè míng fèn quèshí bù yìng gāi nà jīntiān zánmen jiùsuànshì wèi zhè wèi qiánbèi zhèng gè míng dāngnián yóu dī shíyàn de zhēnshí cāozuò zhě zhè wèi mì lìgēn de yánjiūshēng jiàozuò hā wéi·fú lái chè Fletcher měiguó wùlǐ xué jiā qíshí tā zhīhòu de gòngxiàn gèng duō tā zhīhòu yīzhí cóngshì hé shēngxué yǒuguān de yánjiū céngjīng zài bèi’ěr shíyàn shì gōngzuò tā fāmíngliǎo yīgè 2-A tīnglì jì jiùshì yě suàn shì zǎoqí yánjiū diànzǐ zhùtīngqì de rénle tā yīnggāi háishì dì yīgè fāmíngliǎo xiàndài lìtǐshēng lùyīn de rén xiàncún zuìzǎo de lìtǐshēng lùyīn jiùshì yǒu Fletcher tuánduì wánchéng lùzhì de nǐ xiàng wǒmen xiànzài suí suí pián pián dōu néng tīng dào lìtǐshēng yào gǎnxiè zhè wèi Fletcher yīncǐ tā yě bèi rénmen chēng zuò lìtǐshēng zhī fù zhè shì měiguó shēngxué xuéhuì jì àidíshēng zhīhòu de dì èr gè róngyù huìyuán zài 2016 nián Fletcher hái huòdé gé lái měi jiǎng dāngrán shì yǐ gù jiǎng jiùshì wèile jìniàn tā lǎorénjiā zài yīnyuè lìtǐshēng lùzhì fāngmiàn de gòngxiàn yěshì yī wèi chuánqí rénwù shì ba hǎo jīntiān jiù láo dào zhè wǒ shì mā mī shū yīgè jiàozhēn er de lǐgōng nán xiàqī jiàn bàibài

In fact, the instructor basically proposes the topic

Then, after looking forward to doing experiments, recording the data is all the work of graduate students.

The tutor doesn’t care about it

So you really shouldn’t give someone a name

Today, let’s just make a name for this senior

The actual operator of the oil drop experiment that year, the graduate student from Millikan was called

Harvey Fletcher, American physicist

In fact, he contributed more later

He has been engaged in research related to acoustics since then

Used to work at Bell Labs

He invented a 2-A audiometer

That’s one of the early people who studied electronic hearing aids.

He should also be the first person to invent modern stereo recording

The earliest existing stereo recording was completed by the Fletcher team

You can hear stereo sound like we can casually now

Thanks to this Fletcher

So he is also called the father of stereo

This is the second honorary member of the Acoustic Society of America after Edison

In 2016, Fletcher also won the Grammy Award, of course, the late award.

Just to commemorate his old man’s contribution to music stereo recording

Is also a legend, right?

Okay, I’ll be here today

I’m Uncle Mommy, a more serious man in science and engineering

See you in the next issue