Thermodynamics Final Exam multiple choice-Questions and Answers Graded A+

Thermodynamics Final Exam multiple choice-Questions and Answers Graded A+ If the ideal gas law is applicable, we know enthalpy and internal energy are a function of which thermodynamic property? - ANSWER-temperature An open system allows__________to cross the boundary, while a closed system allows_________to cross the boundary. - ANSWER-mass & energy; energy What is the thermal efficiency a heat engine with the following values: Qin=100 Btu, Qout=60 Btu? - ANSWER-n=Wcycle/Qin Wcycle=Qin-Qout 40% If the temperatures of two objects are equal, their internal energies may not be equal. - ANSWER-True What is a thermodynamic process? - ANSWER-How a substance changes from one state to another. What is a thermodynamic state? - ANSWER-The state that a substance is in. i.e. solid, liquid, gas Specific heats relate temperature to what two types of energy? - ANSWER-internal energy & enthalpy Temperature is dependent on material type. - ANSWER-False Referring to the sign conventions of the 1st law of thermodynamics for a control boundary, which of these are positive quantities? - ANSWER-work out & heat in Name the 4 principal temperature scales used: - ANSWER-Fahrenheit, Rankine, Celsius, Kelvin A control volume is a system that..... - ANSWER-allows the transfer of matter across its boundary A system is said to be at___________if none of its properties changes with time. - ANSWER-steady-state A closed system always contains the same matter; there is no transfer of matter across its boundary. - ANSWER-True