If you understand why this is funny, then good, you got something out of this chapter.
I STRONGLY suggest you visit this this web page in order to better understand light waves.
The last couple chapters have given you a lot of information about light, waves, and vibrations. This chapter is very similar to those in the basic nature, so review if necessary, or go back to the previous chapter or two and look at the videos because they apply to light too.
Chapter homework:
6 thru 13;
17 thru 21;
28 thru 36;
40 thru 45.