-
- Part of the challenge is speed, too, how quickly you can get these answers in terms of getting them in on time.
部分困难也会来自于速度，你多快能做出答案,能否在规定的时间做完。
-
I feel like I can, you know, I can decide if I need to run. I can decide if I can slow down,
我感觉我能决定我是否需要小跑。我能决定我是否需要放慢速度，
-
He said, first, let it go a little distance, take the distance over time, that gives you the velocity now.
他说,首先,让它运动一小段距离,距离除以时间,你就能得到现在的速度
-
and we like log algorithms, because they're really fast. A typical characteristic of a log algorithm is a pro-- or sorry, an algorithm where it reduces the size of the problem by a constant factor.
并且我们也很喜欢对数算法,因为它很快,对数算法的典型特性是高速，哦，抱歉，是他能以常数因子的速度,降低问题的大小，很明显。
-
And I could take that information, type it up into a program, make some assumptions about speed and direction and what routes they're going to take and actually watch the ambulance go to St. John's Mercy.
我得到这条信息之后，将它输入程序里，假设它们的速度和方向,以及它们应走哪条线路,就能看到救护车进入圣约翰医院。
-
I hope you didn't mind the enhanced velocity.
我希望你们能适应今天的上课速度。
-
And you can vary the width and the speed and the length.
你能改变它们的广度,速度和长度
-
So, hopefully that kind of clears up that question. And, of course, when the velocity actually is zero, this equation that the de Broglie has put forth is valid for anything that has momentum, so if something does not have any velocity at all, it actually does not have momentum, so you can't apply that equation anyway.
能回答你的问题，当然，如果速度真的是零的话,德布罗意提出的这个方程,只对有动量的物体成立,所以如果一个东西没有速度，它没有动量，也就不能应用这个方程。
-
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
-
What that means is, if you know the velocity of the given time and you know the initial velocity, you know what time it is.
这个方程的意义是,如果你知道某个给定时刻的速度,并且知道初速度,你就能知道运动的时间
-
First, free velocity, constant velocity can be obtained for free without doing anything.
首先,速度是无偿的,恒定速度不需外力作用就能无偿获得
-
Let it go a little more, that gives you the velocity later.
让它再运动一小段距离,那就能得到稍后的速度
-
Another thing you can do is you can find the speed here.
你能做的另一件事就是你可以求出这里的速度
-
That'll give you the velocity.
这样你就能得到速度
-
It's in the nature of things to go at a constant velocity.
能保持恒定速度是物体的固有性质
-
Can you tell me why I'm sure the Earth has an acceleration?
你能告诉我为什么我确信地球有加速度吗
-
The fact that you don't need a force for it to move forever at a given speed in a given direction, that's not obvious, because in daily life you don't see that.
对于物体不需要力的作用就能保持,确定的速度和方向持续运动这一事实,它并非显而易见,因为在日常生活中你看不到这种情况
-
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
-
Once you've got that, one derivative will give you the velocity, then in a crunch you can eliminate t and put it into this formula.
一旦你得到了这个,求一阶导数就能得到速度,然后你可以消去t,把它代入这个式子
-
Second formula tries to relate the final velocity of some time, t, to the initial velocity and the distance traveled with no reference to time.
第二个式子能把某段时间t的末速度,和初速度,经过的路程联系在一起,并且不引入时间
-
take the derivative of this, get the velocity vector and you notice his magnitude is a constant Whichever way you do it, you can then rewrite this as v square over r.
对这个式子求一次导,就能得到速度矢量,你会发现其模长是常数,不管用什么方法,加速度也可以写成 v^2 / r
应用推荐