我们知道，宇宙中只有万有引力和电磁力这两种长程力。

As you know, only universal gravitation and electromagnetic force are long-distance force in the universe.

youdao

我们知道，宇宙中只有万有引力和电磁力这两种长程力。

As you know, only universal gravitation and electromagnetic force are long-distance force in the universe.

youdao