問題一覧
1
Which of the following is the ideal gas law equation ?
PV=nRT
2
during adiabatic, internally irreversible process, what is the true about the change in entropy?
It is always zero
3
How does an adiabatic process compare to isentropic process?
Both: heat transfer = 0; isentropic: reversible
4
Water boils when:
its saturated vapor pressure equals to the atmospheric pressure.
5
How many independent properties are required to completely fix the equilibrium state of a pure gaseous
2
6
In an ideal gas mixture of constituents i and j, what is the mole fraction x, equal to?
Pi/Pi+Pj
7
which of the following is standard temperature and pressure (STP)
0°C and 1 atm
8
Or heat engine operating between temperatures (T2>T1), what is the maximum efficiency attainable?
1-T1/T2
9
what is the value of the work done for our closed, reversible iso metric system?
zero
10
which off the following statement is TRUE for an ideal gas, but not for ideal gas ?
PV=nRT
11
The first law of thermodynamics is based on which of the following principle
Conservation of energy
12
Which of the following cycle is used in the vapor cycle power plant?
Rankine cycle
13
Which ideal cycle below is based on the concept that the combustion process is both diesel and gasoline in the combustion of heat process that is constant pressure and constant volume?
Dual cycle
14
Which of the following is not a thermodynamic property?
Phase
15
Which off the following compressibility factor of ideal gas?
1
16
The energy which includes all of the potential and kinetic energy of the atoms or molecules in a substance is known as ____
Internal energy
17
What refers to the thermodynamic properties which are dependent on the amount of the substance present?
Extensive properties
18
What thermodynamics properties are independent of the amount of substance present?
Intensive properties
19
What is known as the total heat and heat content of why are used times in the history? It also represent the useful energy of a substance.
Enthalpy
20
What is the measure of the energy that is no longer available to perform useful work within the current environment? It is also known as the measure of the randomness of the molecules.
Entropy
21
What is the temperature when water and vapor are in equilibrium with the atmospheric pressure?
Steam point
22
What is the university of Michigan liquid and gases spaces can coexist in equilibrium?
Triple point
23
what refers to the heat needed to change the temperature of the substance without changing its phase?
Sensible heat
24
What is defined as the quantity of heat needed to raise the temperature of 1 kg of water by 1°C?
Kilocalorie
25
What do you call a system in which there is flow of mother through the boundary? This is them usually encloses the device that people must flow, such as : compressor, turbine, or nozzle.
Open system
26
The mechanical equivalent of it is ____
joule
27
The phenomenon of melting under pressure and freezing again when the pressure is reduce is known as:
Regelation
28
What is the entropy of a pure substance at the temperature of absolute zero?
Zero
29
What is the area under the curve on a temperature-entropy diagram?
Heat
30
In a closed vessel,when vaporization takes place the temperature rises. Due to the rising temperature, the pressure increases until equilibrium is established between the temperature and pressure what do you call the temperature of equilibrium?
Boiling point
31
what happens to the internal energy of water at reference temperature were enthalpy zero?
Becomes negative
32
which off the following equation is the definition of enthalpy ?
h=U+PV
33
Which of the following is the work done for a close, reversible, isometric system?
zero
34
Which of the following is the value of N for a perfect gas undergoing an isobaric process?
n=0
35
if an initial volume of an ideal gas is compressed to 1/2 its original volume and to twice its original temperature, the pressure:
Quadruples
36
When the expansion or compression of gas take place without transfer of heat to or from the gas the process is called
Adiabatic process
37
in the absence of any irreversibilities, a thermal electric generator, a device that incorporates both thermal and electric have the efficiency of a/an:
Carnot cycle
38
which of the following best describe both stirling and erickson engines?
External combustion engines
39
Nozzles do not involve any work interaction. The fluid through these device experiences which off the following?
No change in potential energy
40
The convergent section of a nozzle increases the velocity of the flow of the gas. What does it has to do on its pressure ?
it decreases the pressure
41
at steam point, the temperatures of water and its vapor at standard pressure are
In equilibrium
42
In a two piece system, 30% moisture means
70% vapor and 30% liquid
43
The thermal efficiency of gas-vapor cycle is ____ the thermal efficiency of a steam turbine or gas turbine
Greater than
44
A property that indicates the natural direction of a process was first described by a German physicist. this property is called entropy. Who coined the word entropy?
Rudolf Clausius
45
What is the temperature when water vapor are in equilibrium with atmospheric pressure?
Steam point
46
when the expansion over compression of gas takes place "without transfer of heat" to or from the gas, the process is called:
Polytropic
47
What refers to a liquid whose temperature is lower than the saturation temperature corresponding to the existing pressure?
Subcooled liquid
48
Which law that states "entropy of all perfect crystalline solids is zero an absolute zero temperature"?
Third law of thermodynamics
49
What should be the temperature of both water and steam whenever they are present together?
One hundred dergee centigrade
50
Which of the following occurs in a reversible polytropic process?
some heat transfer occurs
51
They change that the system that undergoes from one equilibrium state to another is known as ___
Process
52
What refers to the series of stage through which a system passes during the process?
Path
53
The triple point of a substance is the temperature and pressure at the which
The solid does not melt, the liquid does not boil and the gas does not condense
54
Which of the following relation is not applicable in a free-expansion process
Change in temperature is zero
55
What system in which neither mass nor energy cross the boundaries and it is not influenced by the surroundings?
Isolated system
56
Erickson cycle has:
Two isothermal and two constant pressure processes
57
Stirling cycle has:
Two isothermal and two constant volume processes
58
What is referred to by control volume
Fixed region in space
59
Which of the following is used in thermal power plant
Rankine cycle
60
The elongation and compression of helical spring is an example of which process
Reversible process
61
A bell Coleman cycle is the reverse of which of the following cycles
Joule cycle
62
Brayton cycle has:
Two isentropic and the constant pressure processes
63
Otto cycle consist of :
Two isentropic and two constant volume processes
64
When a system deviates infinitesimally from equilibrium at every instant of its state, it is undergoing what process?
quasi-static process
65
An ideal gas is compressed isothermally. The enthalpy change is
zero
66
The state of thermodynamics system is always defined by its:
Properties
67
entropy is the measure of ?
Randomness or this order
68
What system in which there is no exchange of matter with the surrounding or mass does not cross its boundaries?
Closed system
69
Which one of the choices below refers to a system that is completely impervious to its surrounding or neither mass nor energy cross its boundaries?
Isolated system
70
what refers to a system in which there is a flow of mass across its boundaries
Open system
71
When two bodies, isolated from other environment, are in thermal equilibrium with the third body, the two are in thermal equilibrium with each other. What do you call this statement?
Zeroth law of thermodynamics
72
At equal volume, at the same temperature and pressure conditions, the gases contain the same number of molecules. This refers to which of the following laws?
Avogadro's law
73
In the polytropic process we have pv^n = constant, if the value open is infinitely large, the process is called:
Constant volume process
74
Which of the following cannot be a property of you gas?
Viscosity
75
During adiabatic process, which of the following is the change in entropy?
Zero
76
Which of the following best describe an adiabatic process?
No heat enters or leaves the system
77
Boiling occurs when the vapor pressure attains which of the following pressure?
The ambient pressure
78
Which of the following system where there is no transfer of matter across the boundary? This system consists a fix amount of mass, and no mass can cross it boundary or no mass can enter or leave the system.
Closed system
79
Which of the following values characterize the state of the system?
Property
80
in a complete heat engine cycle, which of the following is area enclosed by PV-diagram?
Work done by the engine per cycle
81
Which of the following engines is least efficient?
Gasoline engine
82
which of the following engines is the most efficient ?
Carnot engine
83
which of the following is the process that cannot be found in a carnot engine cycle?
Isobaric expansion
84
In any process, the maximum amount of heat that can be converted into mechanical energy?
depends on the intake and exhaust temperatures
85
Who coined the word energy?
Thomas Young
86
an ideal heat engine can be 100% efficient only and only if its exhaust temperature is :
0 K temperature
87
What is the most frequent term used in thermodynamic heat engines which indicate how well and energy conversion or transfer process is accomplished?
Efficiency
88
which of the following diagrams was introduced by German scientist R. Mollier?
Enthalphy-entropy (h-s) diagram
89
Which of the following law of thermodynamics which leads to the definition of entropy?
Second law
90
Which of the following is the other term used for enthalpy – entropy (h-s) diagram
Mollier diagram
91
which of the following defines the work output for every heat engine?
Work output is the difference between its heat intake and heat exhaust
92
Which of the following is the value of an (from PV^n=C) for a perfect gas undergoing isothermal process?
1
93
What is used for predicting the behavior of non-ideal gas?
Compressibility factor
94
For any reversible thermodynamic process, which of the following statements is true regarding the change in entropy?
dS>0
95
Which off the following processes where the equation dQ = TdS is applicable
Reversible
96
Which of the following thermodynamic religion is not correct ?
H = U - pV
97
which of the following thermodynamic devices operates the reverse of the heat engine?
Thermal pump
98
What is another term used for isometric processes?
Isochoric process
99
Which of the following engines was introduced by a German engineer, Nickolas Otto?
Gasoline Engine