They built a large road from Boulder City to the area of the dam.

VOA: special.2009.08.12

And if the distance between the wall and the dam was large in comparison to the wavelength then what happens?

如果水槽壁,和屏障之间的距离,大于波长,会导致什么？

麻省理工公开课 - 固态化学导论课程节选

If this distance is large in comparison to the wavelength, this dam simply casts a shadow.

如果这个距离,比波长更长，水槽中的屏障就会投下阴影。

麻省理工公开课 - 固态化学导论课程节选