In the context of moving control volume, which of the following statements is more relevant?

Difference between absolute and relative velocities of fluid is the velocity across moving control volume.

Absolute velocity of fluid carries fluid across the control volume

Control volume is considered as a fixed volume in space

Relative velocity of fluid carries fluid across the control surface of moving control volume

Difference between absolute and relative velocities of fluid is the velocity across moving control volume.

In adiabatic process \(\frac{T_1}{T_2}\) =

\(({\frac{V_2}{V_1}})^{\gamma}\)

\((V_1V_2)^{\frac{\gamma -1}{2\gamma}}\)

\((\frac{P_1}{P_2})^{\frac{\gamma -1}{\gamma}}\)

\(({\frac{V_2}{V_1}})^{\gamma}\)

\((\frac{V_1}{V_2})^{\frac{\gamma -1}{\gamma}}\)

15 + Mcqs in Thermodynamics System And Processes in Thermodynamics Page 1 McqOptions

1.	An ideal gas of mass m is contained in a rigid tank of volume V at a pressure p. During a reversible process its pressure reduces to \(p_2\). Following statements are made regarding the process.(P) Heat is transferred from the gas.(Q) Work done by the gas is zero.(R) Entropy of the gas remains constant.(S) Entropy of the gas decreases.Among the above statements, the correct ones are
A.	P and R only.
B.	P, Q and R only.
C.	Q and R only.
D.	P, Q and S only.
Answer» E.

Discussion

2.	If the value of n is infinitely large in a polytropic process PVn = C, then the process is known as constant
A.	volume
B.	pressure
C.	temperature
D.	entropy
Answer» B. pressure

Discussion

3.	In which process the work-done is zero?
A.	Adiabatic
B.	Isothermal
C.	Isochoric
D.	Isobaric
Answer» D. Isobaric

Discussion

4.	A reversible thermodynamic cycle containing only three processes and producing work is to be constructed. The constraints are: (a) there must be one isothermal process, (b) there must be one isentropic process, (c) the maximum and minimum cycle pressures and the clearance volumes are fixed, and (d) polytropic processes are not allowed. Then the numbers of possible cycles are
A.	1
B.	2
C.	3
D.	4
Answer» E.

Discussion

5.	In the context of moving control volume, which of the following statements is more relevant?
A.	Absolute velocity of fluid carries fluid across the control volume
B.	Control volume is considered as a fixed volume in space
C.	Relative velocity of fluid carries fluid across the control surface of moving control volume
D.	Difference between absolute and relative velocities of fluid is the velocity across moving control volume.
Answer» D. Difference between absolute and relative velocities of fluid is the velocity across moving control volume.

Discussion

6.	In a reversible non-flow process, the gas undergoes a process according to, PV = 2.8Where P is in bar and V is in m3. What will be the work done by the gas if the pressure of the gas increases from 0.7 bar to 7 bar? [Assuming e2.3 = 10]
A.	6.4 kJ
B.	-6.4 kJ
C.	-644 kJ
D.	64 kJ
Answer» D. 64 kJ

Discussion

7.	In adiabatic process \(\frac{T_1}{T_2}\) =
A.	\((V_1V_2)^{\frac{\gamma -1}{2\gamma}}\)
B.	\((\frac{P_1}{P_2})^{\frac{\gamma -1}{\gamma}}\)
C.	\(({\frac{V_2}{V_1}})^{\gamma}\)
D.	\((\frac{V_1}{V_2})^{\frac{\gamma -1}{\gamma}}\)
Answer» C. \(({\frac{V_2}{V_1}})^{\gamma}\)

Discussion

8.	An ideal gas is stored in a piston-cylinder arrangement. If the piston is moved in such a way that the volume of the gas gets doubled at the constant temperature, then the pressure of the gas becomes/remains
A.	Half
B.	Double
C.	4 times
D.	Same
Answer» B. Double

Discussion

9.	A stationary mass of gas is compressed without friction from an initial state of 0.5 m3 to and 0.2 MPa to a final state of 0.3 m3 and 0.2 MPa. Determine the work done by the system.
A.	40 kJ
B.	30 kJ
C.	50 kJ
D.	80 kJ
Answer» B. 30 kJ

Discussion

10.	A perfect gas is compressed to half of its initial volume. This is done using: Process I- Isothermal process and Process II- Polytropic process with index, n = 1.25 Larger work input is required in:
A.	Same in Process I and II
B.	Process II
C.	Process I
D.	Cannot be predicted
Answer» C. Process I

Discussion

11.	A closed bottle filled with water at 0 °C is taken to the surface of moon. If the bottle is opened, the water will
A.	Heat up
B.	Boil
C.	Not undergo any change
D.	None of the above
Answer» C. Not undergo any change

Discussion

12.	A process in which the working substance neither receives nor gives out heat to its surroundings durings its expansion or contraction is called
A.	Isothermal process
B.	Isentropic process
C.	Polytropic process
D.	Adiabatic process
Answer» E.

Discussion

13.	Isochoric process is also known as
A.	Constant volume process
B.	Constant temperature process
C.	Constant pressure process
D.	Constant enthalpy process
Answer» B. Constant temperature process

Discussion

14.	If the change in density occurs at a constant temperature, then the process is called _______ process
A.	Isothermal
B.	Isobaric
C.	Isochoric
D.	Adiabiatic
Answer» B. Isobaric

Discussion

15.	A gas goes through a process given by pv2 = c. It expands from state 1 of 350 kPa and 0.049 m3 to a final pressure of 150 kPa. Work delivered during this process in kJ is:
A.	4.765
B.	8.5
C.	5.915
D.	3.897
Answer» D. 3.897

Discussion

Explore topic-wise MCQs in Thermodynamics.

If the value of n is infinitely large in a polytropic process PVn = C, then the process is known as constant

In which process the work-done is zero?

In the context of moving control volume, which of the following statements is more relevant?

In a reversible non-flow process, the gas undergoes a process according to, PV = 2.8Where P is in bar and V is in m3. What will be the work done by the gas if the pressure of the gas increases from 0.7 bar to 7 bar? [Assuming e2.3 = 10]

In adiabatic process \(\frac{T_1}{T_2}\) =

An ideal gas is stored in a piston-cylinder arrangement. If the piston is moved in such a way that the volume of the gas gets doubled at the constant temperature, then the pressure of the gas becomes/remains

A stationary mass of gas is compressed without friction from an initial state of 0.5 m3 to and 0.2 MPa to a final state of 0.3 m3 and 0.2 MPa. Determine the work done by the system.

A perfect gas is compressed to half of its initial volume. This is done using: Process I- Isothermal process and Process II- Polytropic process with index, n = 1.25 Larger work input is required in:

A closed bottle filled with water at 0 °C is taken to the surface of moon. If the bottle is opened, the water will

A process in which the working substance neither receives nor gives out heat to its surroundings durings its expansion or contraction is called

Isochoric process is also known as

If the change in density occurs at a constant temperature, then the process is called _______ process

A gas goes through a process given by pv2 = c. It expands from state 1 of 350 kPa and 0.049 m3 to a final pressure of 150 kPa. Work delivered during this process in kJ is: