Afour-cylinder, four stroke internal combustion engine has a bore of 12 cm and a stoke of 10 cm in each cylinder. the clearance volume is 12.5% of the cylinder volume at the bottom dead center. the process in each cylinder is modeled as an air-standard otto cycle with a temperature of 300 k and a pressure of 95 kpa at the beginning of compression and the maximum temperature of 1540 k in the cycle. the rate of added heat per unit of mass is 750 kj/kg, during the combustion process. (a) draw the puy diagram of the modeled otto cycle and mark the given temperatures, pressure, and added heat. (b) assume air to be an ideal gas with variable specific heats. (c) find the net work output per unit of mass and solve for the thermal efficiency and the mean effective pressure of the cycle.

Tom is having a problem with his washing machine. he notices that the machine vibrates violently at a frequency of 1500 rpm due to an unknown rotating unbalance. the machine is mounted on 4 springs each having a stiffness of 10 kn/m. tom wishes to add an undamped vibration absorber attached by a spring under the machine the machine working frequency ranges between 800 rpm to 2000 rpm and its total mass while loaded is assumed to be 80 kg a) what should be the mass of the absorber added to the machine so that the natural frequency falls outside the working range? b) after a first trial of an absorber using a mass of 35 kg, the amplitude of the oscillation was found to be 10 cm. what is the value of the rotating unbalance? c) using me-3.5 kg.m, find the optimal absorber (by minimizing its mass). what would be the amplitude of the oscillation of the absorber?