1. A multimode step index fiber has a relative refractive index difference of 2% and core refractive index of 1.48. The maximum optical bandwidth that may be obtained with a particular source on a 5km link is 3Mhz. Determine the rms pulse broadening per kilometre resulting from chromatic dispersion mechanisms. Assuming waveguide dispersion to be negligible, estimate the rms spectral width of the source used, if the material dispersion parameter for the fiber at the operating wavelength is 80 ps nm-1 km-1.
2. A 1km length multimode step index fiber has a spectral width of 50nm with intermodal and intramodal dispersion of 10 ns/km and 100 ps/km respectively. Calculate the total dispersion and maximum bit rate.
2.The relation between electric displacement vector (D), Electric field (E) and Polarization (P)?
An observer with a near point of 25cm looks through a microscope with an objective lens of focal length 1.2cm. when an object is placed 1.28cm from the objective, the angular magnification is -198 and the final image is formed at infinity a. What is the tube length of the microscope b. What is the focal length of the eyepiece