Calculate the diffusion current density for the following carrier distributions. For electrons, use Dn = 35 cm2/s and for holes, use Dp = 10 cm2/s. a. ; Jn = b. , at x = 0: Jp (0) = c. , at x = 2.5 µm: Jp (2.5 µm) = d. , at x = 20 µm: Jp (20 µm) = e. , at x = 5 µm: Jn (5 µm) = n (x) = (1010 cm−3 ) 5 μm − x 5 μm

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.

Slip occurs via two partial dislocations because of (a) the shorter path of the partial dislocation lines; (b) the lower energy state through partial dislocations; (c) the charge balance.

Calculate the bore of a cylinder that has a stroke of 18 inches and an extension time of 6 seconds at a flow rate of 4 gal/min.