So, we can just plug it in. Speed is equal to the distance traveled, which is lambda over the time elapsed, which is 1 over nu. so, we can re-write that as speed is equal to lambda nu times nu, and it turns out typically this is reported in meters per second or nanometers per second.

经过的距离和所花的时间,我们把它们带进来,速度等于经过的距离,也即是lambda除以,所花的时间,通常它的单位,是米每秒或者纳米每秒。

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