And since we are not expecting the mass of the particle to change, what we really are saying is the uncertainty in its velocity times the uncertainty in its position is greater than the ratio of the Planck constant divided by 2 pi.

因为我们不期望,粒子质量发生变化，我们说的是,它速度的不确定度,乘以它位置的不确定度,比普朗克常量,除以2除以圆周率要大。

麻省理工公开课 - 固态化学导论课程节选

So, this is the most general position for a particle of constant acceleration, a.

这是一个加速度为a的匀加速质点,位移的最一般的表达式

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So, the question we are going to ask is the following, "If I tell you that a particle has a constant acceleration a, can you tell me what the position x is?"

接下来要问的问题就是,如果我说某质点加速度恒为a,你能告诉我它的位移x是多少吗

耶鲁公开课 - 基础物理课程节选

The MIT Campus Police are in the constant position of figuring out whether or not to put a stop to the pranks, or to let them happen as long as everyone is kept safe.

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This is where money management is key: position-sizing requires constant adjustment, especially during periods of wide variance.

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This tells you how much information is present at each position: variable positions contain little information while constant positions contain lots.

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