因为电动马达的最大力矩处于零速度。

Because the most torque an electric motor has is at zero speed.

youdao

也许是这里零速度，释放，也许给它一个初速度。

Maybe it's just that I release it here; with zero speed; maybe I give it a little speed.

youdao

要求此电源能输出任意形状的矩形波，交流正负极性比率可任意调节，交流过零速度极快。

Rectangular wave of arbitrary shape shall be output, change rate of AC plus-minus shall be regulated arbitrarily, and the speed of exchanges over zero shall be very quick.

youdao

That's the point where velocity is 0.

也就是速度为零的点

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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。

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