A light pulse with wavelength 850 nm passes through a single-mode silica fiber.

(a) Determine the time spread of the pulse per unit length due to material dispersion if the spectral width is 20 nm.

(b) Repeat if the spectral width is 2 nm.

What precautions should you take to prevent injuries when dealing with heavy loads?

Aloaded platform of total mass 500 kg is supported by a dashpot and by a set of springs of effective stiffness 72 kn/m. it is observed that when the platform is depressed through a distance x = 12.5 cm below its equilibrium position and then released without any initial velocity; it reaches its equilibrium position in the shortest possible time without overshoot. find the position and velocity of the loaded platform 0.10 sec. after its release. if a further load of 400 kg is added to the platform, find, i) the frequency of damped vibrations, and i) the amplitude of vibration after 2 complete oscillations, given that the initial amplitude is 15 cm.

Acompressor receives the shaft work to decrease the pressure of the fluid. a)- true b)- false