如果这是物体-，你可以想成，在地球上，如果你想-，这里有个物体，我必须知道这两个，物体之间的力是什么。

M if this is an object, capital m — and you can think of this as being the Earth, - if you want to — m and there is here an object little m, then I have to know what the forces are between the two.

youdao

如果这是物体-，你可以想成，在地球上，如果你想-，这里有个物体，我必须知道这两个，物体之间的力是什么。

M if this is an object, capital m — and you can think of this as being the Earth, - if you want to — m and there is here an object little m, then I have to know what the forces are between the two.

youdao