The Electromagnetic Spectrum 101 Last updated Save as PDF Page ID185297 To Do To Answer Read about the electromagnetic spectrum Describe the each portion of the electromagnetic spectrum. How is each used in your everyday life? How is each portion difference from one another? How is electromagnetic radiation measured? Why are telescopes put into orbit? Define wavelenth, speed, wave and frequency. Work through the Doppler Effect interactive Describe how the Doppler Effect works? Why is the Doppler Effect used in astronomy? How and why are absorption lines read?