你用拇指发短信的速度快吗？

Are you fast at writing the messages with your thumb?

youdao

那么，你用拇指输入信息的速度快吗？

So are you fast at writing the messages with your thumb?

youdao

Finke的方案强调“基于努力的训练”，他认为应在大多数情况下保持最适度的努力（用80%的速度你也可以跑相同的距离）。

The Finke program emphasizes "effort-based training, " and he believes in keeping the effort modest (at 80 percent of the speed you could race the same distance) most of the time.

youdao

It's useful to have the average acceleration, which you can find by taking similar differences of velocities.

平均加速度也是很有用的,你可以用类似方法,取速度的变化量求出来

耶鲁公开课 - 基础物理课程节选

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

耶鲁公开课 - 基础物理课程节选