When an electric field is applied at one end, DNA molecules will move across the surface and collide with the obstacles, impeding their motion.
当在一个终端加上一个电场时，DNA分子将穿过表面并和障碍物碰撞，以致阻碍了它们的行动。
And we are led to infer that, if all the impeding forces of gravitation and resistance could be removed, there is no reason why the ball, once in motion, should ever stop.
由此可以推论，如能去除一切起阻碍作用的引力和阻力，就没有理由认为，球一旦处于运动中还会再停下来。
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