The fuel of problem 4 was used to run a spark-ignition engine in a laboratory environment simulating the atmosphere of planet Mars. The intake air was composed of (O2 + 3CO2). Stoichiometric amounts of "air" and fuel enter the engine at 25°C, while combustion products in the exhaust manifold are at an average temperature of 1000 K. Only products of complete combustion are found in the exhaust. It is measured that the engine produces 2.0 kW of power while the heat transfer rate to the surroundings is 1.0 kW.

a) Determine the mass flow rate of the fuel supplied to the engine.

b) Determine the fuel conversion efficiency of the engine when operated with the proposed fuel.

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?