Hello guys I am taking electro optic this semester. . I had a quiz last friday. I could not do couple of questions. 1.The reason of the 1550 nm fiberoptic systems are more populer than 1300nm is, 1550 has less attenuation? 2.What is the aprroximate value of the loss of present day fiber optic systems in terms of db/km at 850nm and 1550nm? 3. why can we not measure the phase difference between two light beams electronically. 4. I have fiber optic sensor which is extremely high sensitive. What kind of light source should I use and why? interferometric sensor, and I said Laser source but i dont know why Well thanks alot if you help me to solve these questions.