Question

container is heated by the sun. There is no shaft work associated with the contalner. From the 1- Law of Thermod be aJEqual to the heat transfer bJEqual to the change in internal energy cJEqual to the volume times the change in pressure ynamics, you determine the resulting work to d)Equal to zero e)Equal to the change in enthalpy re actual devices such as turbines, nozzles, and diffusers to ideal ones. Which statement is true? The isentropic efficiency is used to compa a)Only the ideal device is considered adiabatic bjThe Inlet state and exit pressure are the same for both the ideal and actual device cJThe ideal device operates irreversibly d)The efficiency can be greater than one e)Nelther device is adiabatic In an ideal refrigeration cycle, liquid leaves the condenser and is expanded in such a manner that the enthalpy of the liquid is equal to the enthalpy of the resulting saturated mixture. This type of expansion is known as a)A throttling process bJAn isothermal process cJA compression process dJAn isochoric process eJA reversible process For an ideal turbjoet, all of the following statements are true EXCEPT b)The efficiency of the compressor is 100% a)The efficiency of the turbine is 100% c)The work produced by the turbine is greater than the work required by the d)The efficiency of the nozzle is 100% An ideal gas is contained in a rigid container. There is no work of a rotating shaft associated with the container. Any heat transfer is a function of a)Pressure only b)Volume only c)Temperature only d)The heat transfer will be equal to the work

Answer 1

1. Since the container is rigid , so change in volume will be zero and also there is no shaft work. So, work will be zero.So,option D is correct.

2.The inlet state and outlet pressure will be same...so option B.

3. Throttling process , so option A

4. The work by turbine is equal to the work needed by compressor, so, option C

5. Since there is no work, so heat transfer is equal to the change in internal energy, so ,it will be function of temperature only

so option C