What is the meaning of "the length of a wave" according to paragraph 3?

根据第三段，“the length of a wave” 是什么意思？

youdao

What is the meaning of all this?

这一切是什么意思？

youdao

What is the meaning of this gross outrage?

这种粗暴的行径是什么意思？

youdao

Lincoln feels that what he is doing will give the war effort new meaning.

VOA: special.2010.05.10

What is the meaning of an untrodden way, or of "there are none to praise" her but "very few to love"?

没有人走过的路是什么意思呢？,还有“没有人赞扬她“但是“几乎没有人爱她“又是什么意思呢？

耶鲁公开课 - 文学理论导论课程节选

the Thompson is sent with a mission to find out what is the meaning of rosebud ? what was rose then?

汤普森是有任务而去的,他的任务是找出玫瑰花蕾的含义,那么玫瑰又是指什么？

麻省理工公开课 - 电影哲学课程节选

Anyway, what is the meaning of an overall figure that makes no distinction between a dope-smoking student, a recidivist rapist and a financial trickster (white-collar crimes increased by almost 4%)?

ECONOMIST: Crime in France

The personal questionnaires ask simple questions like what are you doing right now, who are you with, what is the meaning of this experience to you, and does it make you happy.

FORBES: New Project Wants to Know What Gets You Happy and Make it Happen

What is the meaning of my life now?

CNN: 2 would-be passengers feel relief, sadness: 'It could have been me'