Light and Waves
Article - https://www.wwu.edu/astro101/a101_lightwaves.shtml#text=Light%20radiates%20from%20a%20source,light%20is%20called%20Electromagnetic%20Radiation.&text=The%20shortest%20wavelengths%20of%20the,%2Dray%2C%20and%20gamma%20radiation.
Physics CrashCourse (More than Needed) - https://www.youtube.com/watch?v=IRBfpBPELmE
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