Carnot heat engine receives 612 kJ of heat per cycle from a high temperature source at 577°C and rejects heat to a low-temperature sink at 43°C. Determine the amount of heat rejected to the sink per cycle.

1. An engine with a cylinder volume of 250 cc and a volume at top dead centre of 25 cc uses a thermal cycle where the initial stage is an isentropic adiabatic compression process with the equation pvY = C. It is known that the initial conditions are 1 bar and 30°C. After that, a combustion process takes place in which heat is supplied at a constant volume. The heat given is 80 KJ/kg and if the specific heat at constant volume is known to be 0.718 kJ/kg K, determine the maximum temperature and pressure that occur? 2. Air with a mass of 3 kg is heated at constant volume from 25°C to 120°C. The process then takes place at constant pressure so that the gas has a temperature of 550°C. Determine the heat required and the entropy change that occurs during the process? (Air: Cp = 1.005 kJ/kg.K and y = 1.4; and assume Cp does not change with temperature). Known that initial volume is 50 ml and the last volume is 300 ml.

As shown in the figure, an air conditioner operating at steady state maintains a dwelling at 70°F on a day when the outside temperature is 103.5°F. The rate of heat transfer into the dwelling through the walls and roof is 30,000 Btu/h and the net power input to the air conditioner compressor is 3.45 hp. Step 1 B Inside, 70° F Determine the coefficient of performance for the air conditioner. = Evaporator i 30,000 Btu/h Determine the coefficient of performance of the air conditioner. Determine the power input required, in hp, and the coefficient of performance for a reversible air conditioner providing the same cooling effect while operating between the same cold and hot temperatures. Refrigerant loop Compressor Outside Q + Condenser

Heat transferred from the higher and lower temperature reservoirs are  and , respectively. Select the thermal efficiency  for a heat engine___________    A. 0.5   B. 2.0    C. 1.5    D. 0.67