# Pinyin/Principle Of Relativity

In the Physics of Aristotle, heavy objects fall faster than objects that are not heavy. The natural science of Aristotle was most popular in Western thought for 2,000 years.

Zài Aristotle de wùlǐxué, zhòngwù zhuìxià bǐ bù zhòng de wùtǐ kuài. Aristotle de zìrán kēxué yǒu 2000 nián lìshǐ, shì zuì liúxíng de Xīfāng sīxiǎng.

Galileo proved that all objects fall with the same acceleration. Therefore, the longer an object moves with constant acceleration the faster its final velocity is. Also, if different objects each having a different mass are dropped from rest (initial velocity is zero) at the same height in a vacuum, they will all hit the ground at the same velocity regardless of their mass. The experimental discoveries of Galileo and the Laws of Motion developed mathematically by Newton gave birth to modern science.

Galileo zhèngmíng, suǒyǒu wùtǐ yǐ xiāngtóng de jiāsùdù zhuìxià. Yīncǐ, wùtǐ yǐ héngdìng de jiāsùdù yídòng yuè cháng, qí zuìzhōng sùdù yuè kuài. Rúguǒ bùtóng zhìliàng de wùtǐ, zài tóngyī gāodù de zhēnkōng, cóng jìngzhǐ (chūshǐ sùdù wéi líng) zhuìxià; jǐnguǎn tāmen de zhòngliàng bùtóng, dōu jiāng yǐ xiāngtóng de sùdù jīzhòng dìmiàn. Galileo de shíyàn fāxiàn, hé Newton yǐ shùxué yǐnzhèng de yùndòng dìnglǜ, cuīshēngle xiàndài kēxué.

Galileo's principle of relativity states "It is impossible by mechanical means to say whether we are moving or staying at rest". If two trains are moving at the same speed in the same direction, then a passenger in either car will not be able to notice that either train is moving. However, if the passenger takes a fixed frame of reference, a fixed point, like the earth, he will then be able to notice the motion of either train. Another thing, if one stands on the earth one will not be able to see that it is moving.

Galileo de xiāngduì zhuàngtài yuánlǐ “yòng jīxiè zhuāngzhì bùnéng shuōmíng wǒmen shìfǒu zài yùndòng huò jìngzhǐ”. Rúguǒ liǎnggè lièchē zài xiāngtóng de fāngxiàng yǐ xiāngtóng de sùdù yídòng, zé zài rènyī chēxiāng nèi de chéngkè jiāng wúfǎ zhùyì dào rènyī lièchē zhèngzài yídòng. Dànshì, rúguǒ chéngkè yǒu gùdìng de cānkǎo kuàngjià, yīgè gùdìng de diǎn, rú dìqiú, tā jiāng nénggòu zhùyì dào rènyī huǒchē de yùndòng. Lìngyī fāngmiàn, rúguǒ shēnchǔ dìqiú, shì wúfǎ kàndào tā zhèngzài yídòng.

This principle is just taken from observation. For example, if we are travelling by airplane at a constant speed, we can walk through the inside of the airplane without noticing anything special.

Zhèyī yuánlǐ zhǐshì cóng guānchá dédào. Jǔlì láishuō, rúguǒ wǒmen chéng fēijī yǐ héngdìng sùdù xíngshǐ, wǒmen kěyǐ zài fēijī nèi zǒudòng, ér méiyǒu zhùyì dào shénme tèbié de.