A simple Brayton cycle using air as the working fluid has a pressure ratio of 10. The minimum and maximum temperatures in the cycle are 295 and 1240 K. Assuming an isentropic efficiency of 83 percent for the compressor and 87 percent for the turbine, determine (a) the air temperature at the turbine exit, (b) the net work output, and (c) the thermal efficiency.

A Carnot cycle is a thermodynamic process consisting of four stages: 1) isothermal expansion; 2) adiabatic expansion; 3) isothermal compression; and 4) adiabatic compression back to the original state. Assuming you have 1.00 mol of a monatomic ideal gas at standard state and the volume is doubling during stage 1 (isothermal expansion), calculate the change in internal energy for this part of the Carnot cycle. A)22.4 J B) 2.27 kJ C)-2.27 kJ D)-1.72 kJ E)0 J     For the same system as in Question ^, calculate the change in temperature for the second stage (adiabatic expansion), assuming that the volume doubles yet again (that is, it is twice as large as the volume at the end of stage 1 but four times greater than the initial volume at the beginning of stage A) 0K B) 188K C) -188K D) -110K E) 110K

Air is compressed steadily by a compressor from 100 kPa and 17C to 700 kPa at a rate of 5 kg/min. Determine the minimum power input required if the process is (a) adiabatic and (b) isothermal. Assume air to be an ideal gas with variable specific heats, and neglect the changes in kinetic and potential energies.

Consider the following thermodynamic cycle for an ideal gas: From A to B the gas is compressed adiabatically. From B to C heat Qh is added to the gas and the gas is kept at constant volume. From C to D the gas expands adiabatically. From D to A the gas ejects heat Q₁ to the environment and is kept at constant volume. (1) Draw the PV-diagram associated to this cycle. (2) Show that the efficiency of an engine running this cycle is given by e = 1 - (3) Calculate the efficiency for a compression ratio VA/VB = 8 assuming a diatomic gas. [Hint: for a diatomic gas Cv = (5/2)R.]