2015.05.05【英译中】简明科技知识问答手册——物理和化学(2)

yangf2014 (不灭孽蜥) 译译生辉
11 1 0
发表于:2015-05-05 12:46 [只看楼主] [划词开启]

What is inertia?

什么是惯性?

       Inertia is a tendency of all objects and matter in the  universe to stay still,or if moving,to continue moving,to continue moving in the same direction,unless acted on by some outside force.This forms the first law of motion formulated by Isaac Newton(1642-1727).To move a body at rest,enough external force must be used to overcome the object`s inertia;the larger the object is,the more force is required to move it.In his Philosophae Naturelis Principia Mathematica,published in 1687,Newton sets forth all three laws of motion.Newton`s second law is that the force to move a body is equal to its mass times its acceleration(F=MA),and the third law states that for every action there is an equal and opposite reaction.

       惯性是指保持宇宙中一切物体和物质的趋势,或者说当物质运动时能持续运动,并在同一个方向下运动,除非受到其他力的干扰。这一运动第一定律是由艾萨克·牛顿(1642-1727)所建立。要使一个静止的物体运动,就必须有足够的外力克服物体惯性;物体越大,所需要外力越大。在牛顿1687年出版的自然哲学的数学原理中,牛顿 建立了运动三大定律。牛顿第二定律是推动这个物体所需要的力等于它的质量乘以加速度(F=MA),而牛顿第三定律则声明任何动作都是由一对大小相等,方向相反的作用力与反作用力组成的。

Why does a boomerang return to its thrower?

为什么回旋镖投出后能回到投掷者手中?

       Two well-known scientific principles dictate the characteristic flight of boomerang:(1)the force of lift on a curved surface caused by air flowing over it;and (2) the unwillingness of a spinning gyroscope to move from its position.

       众所周知,回旋镖遵循着两个科学原理:(1)作用在曲线上的胜利是克服空气流动时获得的。(2)不管你愿不愿意,它都是旋转着离开自己的位置。

       When a person throw a boomerang properly,he or she causes it to spin vertically.As a result,the boomerang will generate lift,but it will be to one side rather than upwards.As the boomerang spins vertically and moves forward,air flows faster over the top arm at a particular moment than over the bottom arm.Accordingly,the top arm produces more lift than the bottom arm and the boomerang tries to twist itself,but because it is spinning fast,it acts like a gyroscope and turns to the side in an arc.If the boomerang stays in the air long enough,it will turn a full circle and return to the thrower.Every boomerang has a built-in orbit diameter,which is not affected by a person throwing the boomerang harder or spinning it faster.

       如果一个人以正确的姿势投掷回旋镖,他或者她会抛出垂直方向上旋转的回旋镖。结果,回旋镖会升起,但会偏向一边而不是两边同时向上。当回旋镖垂直方向上旋转并且移动时,空气在某一时刻上臂比下臂流动得更快。所以,上臂比下臂获得更大的升力,虽然回旋镖试着自转,但是因为它旋转得太快,就像在空中划出一道弧飞回来。如果回旋镖在空中呆的够久,它就会旋转一个圆圈回到投掷者手中。每个回旋镖在制作出来时都有自己的轨道半径,不会因为人投掷时的力道或是旋转时更快而改变。

分类: 英语
全部回复 (1)

  • 0

    点赞

  • 收藏

  • 扫一扫分享朋友圈

    二维码

  • 分享

课程推荐

需要先加入社团哦

编辑标签

最多可添加10个标签,不同标签用英文逗号分开

保存

编辑官方标签

最多可添加10个官方标签,不同标签用英文逗号分开

保存
知道了

复制到我的社团