根据它的原理，我们通常用v表示,这里的V更代表速率而不是矢量，你能通过,对一个关于时间的位置向量求导得到它。

And, the way we can get it, so, it's called usually V, so, V here stands for velocity more than for vector. And, you just get it by taking the derivative of a position vector with respect to time.

youdao

您的代码应该在开启了垂直同步以及关闭缓冲的前提下、能够保持运行时帧速率等于或大于Rift头盔显示屏刷新率。

Your code should run at a frame rate equal to or greater than the Rift display refresh rate, v-synced and unbuffered.

youdao

金的填隙原子向硅扩散的速率比III族和v族杂质快几个数量级。

The interstitial atoms of gold diffuse into silicon at a rate several orders of magnitude faster than the group III and V impurities.

youdao

And if we talk about electrons or photoelectrons, again we can describe it in terms of energy, we can talk about velocity, and from there, of course, you can figure out the energy from 1/2 m v squared, and actually we can also describe the electron in terms of wavelength.

如果我们谈论电子或者光电子，我们又可以从能量的角度来描述它，我们可讨论速率，从那里，当然，你可以计算1/2，m，v2得出能量值，而且事实上我们也可以,从波长的角度来描述电子。

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