Now, I know that momentum is zero, so I only can write down for this situation after the collision m1 0 plus m2 times u2 prime must be zero.

动量为，我只能写下这种情况,在碰撞之后,乘以u1’，that，m1，times，u1，prime,加m2乘u2’必为。

youdao

Well, before, the speed is zero and so the momentum is zero. And there comes the bang and one piece flies in this direction with a certain velocity, v2 prime.

在之前，速度为，动量也为0，现在砰响了一声，一片朝这个方向飞，它的速度为v2。

youdao

If you know your atoms are inside your experiment, there must be some uncertainty in their momentum keeping them above absolute zero - unless your experiment is the size of the whole universe.

如果你知道在你的实验装置中的原子，它们就必然具有某些动量的不确定性使得这些原子的温度高于绝对零度，不然的话，只有你的实验装置的尺度达到了整个宇宙。

youdao

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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