2.13. Nitrogen, traveling at 12 m/s with a pressure of 14 bar abs. at a temperature of 800 K, enters a device with an area of 0.05 m2 . No work or heat transfer takes place. The temperature at the exit, where the area is 0.15 m2 , has dropped to 590 K. What are (a) the velocity and (b) pressure at the outlet section?

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.