The National Highway Traffic Safety Administration has linked more than 50 deaths to the unexpected acceleration problems -- a safety issue Toyota has blamed on floor mats and sticky gas pedals.

VOA: standard.2010.03.26

And bathing inside the inner ear fluids where they become stimulated by sound waves and acceleration forces.

毛细胞悬浮在内耳液中,接受声波和其它外力的刺激。

斯坦福公开课 - 7个颠覆你思想的演讲课程节选

Now, gravity, well force, is equal to mass times acceleration, g and the acceleration due to gravity is g.

是重力，等于质量乘以加速度，由重力导致的加速度是。

麻省理工公开课 - 热力学与动力学课程节选

Take the difference of the two velocities and divide by the difference of the two times, and you've got the acceleration.

求出速度的差值,除以时间的差值,这样就能得到加速度

耶鲁公开课 - 基础物理课程节选

And, you know acceleration means either change of speed or change of direction.

你知道加速度意味着,不是改变速度就是改变方向。

麻省理工公开课 - 固态化学导论课程节选

The government has liberized the economy and that has of course been playing a role but the growth acceleration started almost a decade before that, so the factors are a little more complex.

印度政府让经济自由发展,这一决策显然是起了作用的,但在这一决策出现约10年前,印度经济的加速发展便开始了,所以经济腾飞的原因还比较复杂。

普林斯顿公开课 - 国际座谈会课程节选

But the acceleration it produces on the elephant and on the mass, are in an inverse ratio of their masses.

但这个力使大象和物体产生的加速度,与它们的质量成反比

耶鲁公开课 - 基础物理课程节选

And know intuitively that if they move together, they will behave like an object of mass 5 and the acceleration will again be 2.

凭直觉认为既然它们一起运动,那么它们就相当于一个质量为 5 千克的物体,然后我们可以算出加速度为 2

耶鲁公开课 - 基础物理课程节选

Now I can measure that, because I pull it by one centimeter and I find the acceleration it exerts on a known mass.

现在就能测量这个力了,因为把弹簧拉伸 1 厘米,我就知道它让一个质量已知的物体产生的加速度

耶鲁公开课 - 基础物理课程节选

It says that, "If a body has an acceleration, then you need a force and the relation of the force to acceleration is this thing."

它是这么说的,"如果一个物体有加速度,那么你需要有一个力,力和加速度的关系是这样的"

耶鲁公开课 - 基础物理课程节选

He just said whenever there's an acceleration, it's going to be due to some forces and it's your job to find what the forces are.

他只说过只要有加速度,就说明有力的作用,你们的任务是要找出这些力

耶鲁公开课 - 基础物理课程节选

As you start on the top and go down, your acceleration is negative.

当你在顶楼准备下降的时候,你的加速度是负的

耶鲁公开课 - 基础物理课程节选

Then you guys know, you just told me, acceleration is -9.8, We call it "minus" because it's accelerating down and up was taken to be the positive direction.

然后你们都知道,你告诉我,加速度是-9.8,我们取负号是因为加速度方向朝下,而正方向为竖直向上

耶鲁公开课 - 基础物理课程节选

If I pull the one kilogram mass and I let it go, it does something, some acceleration.

如果我拉 1 千克重的物体并松手,就会获得一个加速度

耶鲁公开课 - 基础物理课程节选

This particle is constantly changing its direction, but it therefore has an acceleration and the acceleration, we have shown here, is pointing towards the center.

这个质点恒定地改变它的运动方向,因此它具有加速度,而且这个加速度,我们前面也讲过了,指向圆心

耶鲁公开课 - 基础物理课程节选

But if you imagine making these measurements more and more and more quickly, in the end, you can measure what you can say is the acceleration now.

但如果你想越来越短的时间内,测量这些数据,最终,你会测量出你所说的现在的加速度

耶鲁公开课 - 基础物理课程节选

Force causes acceleration and this is a precise statement.

力产生了加速度,这是一个精确的说法

耶鲁公开课 - 基础物理课程节选

Once you can take one derivative, you can take any number of derivatives and the derivative of the velocity is called the acceleration, and we write it as the second derivative of position.

只要你能求一阶导数,你就能求任意阶的导数,速度的导数被称为"加速度",我们把它写成位移的二阶导数

耶鲁公开课 - 基础物理课程节选

You cannot say to me, "Take a force, due to a spring, and see what force it applies and divide by the acceleration and get the mass, " because we haven't defined force, either.

你不能说,"给弹簧施加一个力,看看它能提供多大的力,然后除以加速度,得到质量",因为我们还没给力下一个定义

耶鲁公开课 - 基础物理课程节选

Then, I bring the elephant and I pull the spring by the same amount and I find the acceleration of the elephant and the denominator is obviously the mass of the elephant.

然后我再找来大象,用相同的力去拉弹簧,大象就具有了加速度,很明显,分母就是大象的质量

耶鲁公开课 - 基础物理课程节选

It knows that this particle happened to have a height of 15, at the time of 0, and a velocity of 10, and it is falling under gravity with an acceleration of -10.

这个质点恰好处在高度为15的地方,零时刻,初速为10,并在重力作用下以-10的加速度下坠

耶鲁公开课 - 基础物理课程节选

Then the acceleration of the planet is the force of gravity between the planet and the Sun, which Newton will tell you is directed towards the Sun and it depends on how far you are.

行星的加速度源自,行星和太阳之间的作用力,牛顿认为这个力指向太阳,它的大小取决于行星离太阳有多远

耶鲁公开课 - 基础物理课程节选

That's how by either balancing the unknown force with a known force or by simply measuring the acceleration as I fall towards this podium and multiplying by mass, you can find the force that exerts on me.

我们既可以让未知力与已知力平衡,也可以只测量我冲向讲台时加速度的大小,再与我的质量相乘,都能求出作用在我身上的力的大小

耶鲁公开课 - 基础物理课程节选

If your plan is to accelerate a 3 kg mass with an acceleration of 2 meters per second, you better have a rope that can furnish that force and it can take the tension of 6 Newtons.

如果你想用 2 米每秒平方的加速度,去拉一个 3 千克的物体,那么你就需要一根能提供拉力的绳子,并且它能够承受 6 牛的张力

耶鲁公开课 - 基础物理课程节选

At any point on the graph you can take the derivative, which will be tangent to the curve at each point, and its numerical value will be what you can call the instantaneous velocity of that point and you can take the derivative over the derivative and call it the acceleration.

在图上的任意一点,你可以进行求导,得到曲线上每一点的切线斜率,所得到的数值,即为该点处的瞬时速度,然后你再求一次导,得出它的加速度

耶鲁公开课 - 基础物理课程节选

Even at=0, and it has an initial velocity, so even without any acceleration, it will be moving from y0 to y0+vt.

即使at=0,它仍然有初速度,因此即使加速度为0,它也会从y0运动到y0+vt

耶鲁公开课 - 基础物理课程节选

You're only given the particle has acceleration a, and you are asked to find out what is x?

你只知道质点的加速度为a,你需要求出x是多少

耶鲁公开课 - 基础物理课程节选

That means the acceleration is pointing towards the center of the circle and it has a magnitude a.

也就是说加速度,始终指向圆心,其模长为 a

耶鲁公开课 - 基础物理课程节选

You can take a derivative of the derivative and you can get the acceleration vector, will be d^2r over dt^2, and you can also write it as dv over dt.

你可以对导数再求一次导,你就可以得到加速度矢量,也就是 d^2 r / dt^2,你也可以写成 dv / dt

耶鲁公开课 - 基础物理课程节选

I know this is the right answer, because if I now find the acceleration, I find it's mg divided by m and I get -g as the answer for all bodies.

我知道这个等式是正确的,因为现在如果我要求物体的加速度,用 mg 除以 m,我就得到 -g,这个结果对所有物体都成立

耶鲁公开课 - 基础物理课程节选