Since you know the velocity of the transmitter from this ratio since you know the period, R which is this, you now also find the radius R.

既然根据这个比例,知道了发射机的速度,既然你们知道了周期，就是这个，也就知道了半径。

youdao

R If you know the radius r, then, of course, the velocity of the astronauts follows immediately.

如果知道半径，两个宇航员的，速度也能马上算出来。

youdao

r So, let's remember that the amount by which we moved, t delta r, is approximately equal to v times delta t, OK, and just using the definition of a velocity vector.

所以记住移动的量△,约等于v*△,这是用速度矢量的定义。

youdao

Now, you can take this velocity, you can take this R.

现在 你已有了速度和 R

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