Problem 9.011 si consider a modification of the air-standard otto cycle in which the isentropic compression and expansion processes are each replaced with polytropic processes having n = 1.3. the compression ratio is 8 for the modified cycle. at the beginning of compression, p1 = 1 bar and t1 = 310 k. the maximum temperature during the cycle is 2200 k. determine: (a) the heat transfer and work in kj, for each process in the modified cycle. (b) the thermal efficiency. (c) the mean effective pressure, in bar.

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.

Fluids at rest possess no flow energy. a)- true b)- false

An engine runs on the ideal diesel cycle. the cycle has a compression ratio of 20 and a cutoff ratio of 2. the highest temperature in the cycle is 1200 k. if the heat into the system is 300 kj/kg of working fluid and using variable specific heats determine the work produced per mass of working fluid