ENGR 130 MIDTERM 2 2025/2026 EXAM
QUESTIONS AND ANSWERS | 100%
PASS
Air is flowing in a pipe with 0.2 m in diameter at an average velocity of 0.1
m/s. The density of air is 1.754 kg/m3. What is the mass flow rate? -
🧠ANSWER ✔✔0.0055 kg/s
Reason:
m⋅ = ρVavgAc, Ac = πD^2/4
A nozzle is considered to be a steady flow device where a single stream
flows in and out. Steam with a density of 1.91 kg/m³ with an average
velocity of 122 m/s flows into a nozzle. Its inlet area of the nozzle is 104 ×
10^−4 m^2. Determine its mass flow rate at the nozzle outlet. - 🧠ANSWER
✔✔2.42 kg/s
,Reason:
m∙in =m∙out =ρVavgA
True or false: Flow work can be expressed in terms of other properties. -
🧠ANSWER ✔✔True
Which of the following energies are part of the total energy of a flowing
fluid? - 🧠ANSWER ✔✔Enthalpy
Kinetic energy
Potential energy
Which of the following statements are true? (Select all that apply.) -
🧠ANSWER ✔✔-the steady-flow process is a process during which a fluid
flows through a control volume and does not change with time-during a
steady flow process, boundary work is zero-the steady flow implies that the
fluid properties can change from point to point, but at any point, they
remain constant during the entire process
The volumetric flow rate of water flowing through a pipe is 5 L/s, and the
density of water is 1 kg/L. What is the mass flow rate? - 🧠ANSWER ✔✔5
kg/s
,Reason:
Mass flow rate is equal to the product of density and volumetric flow rate.
True or false: In a single-stream, steady flow system, the mass flow rates
for the inlet and outlet must be the same. - 🧠ANSWER ✔✔True
Which of the following statements are true? (Select all that apply.) -
🧠ANSWER ✔✔-The rate of change of mass within a control volume minus
the net flow rate in and plus the net flow rate out of the control surface must
equal to zero.
-In a steady flow process, the total rate of mass entering a control volume
is equal to the total rate of mass leaving it.
In an open system, when mass flows across control volume boundaries,
some work is required to push the mass into or out of the control volume,
and this is known as ______ work. - 🧠ANSWER ✔✔flow
In a steady flow process, energy can be transferred by ______. -
🧠ANSWER ✔✔work, mass, and heat
True or false: The total energy for a flowing fluid consists of an additional
term when compared with the total energy for a nonflowing fluid.
3
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
, True false question. - 🧠ANSWER ✔✔True
During a steady-flow process, the fluid properties at an inlet or exit must
______. - 🧠ANSWER ✔✔remain constant
Nozzle
matches
Choice, A device that increases the velocity of a fluid at the expense of
pressure
A device that increases the velocity of a fluid at the expense of pressure
Diffuser
matches
Choice, A device that increases the pressure of a fluid by slowing it down
A device that increases the pressure of a fluid by slowing it down -
🧠ANSWER ✔✔hi
In a single-stream, steady flow system, the mass flow rate can be defined
as the product of ___________, __________, and ___________. -
🧠ANSWER ✔✔Density, velocity, and area
Turbine - 🧠ANSWER ✔✔produces shaft work
QUESTIONS AND ANSWERS | 100%
PASS
Air is flowing in a pipe with 0.2 m in diameter at an average velocity of 0.1
m/s. The density of air is 1.754 kg/m3. What is the mass flow rate? -
🧠ANSWER ✔✔0.0055 kg/s
Reason:
m⋅ = ρVavgAc, Ac = πD^2/4
A nozzle is considered to be a steady flow device where a single stream
flows in and out. Steam with a density of 1.91 kg/m³ with an average
velocity of 122 m/s flows into a nozzle. Its inlet area of the nozzle is 104 ×
10^−4 m^2. Determine its mass flow rate at the nozzle outlet. - 🧠ANSWER
✔✔2.42 kg/s
,Reason:
m∙in =m∙out =ρVavgA
True or false: Flow work can be expressed in terms of other properties. -
🧠ANSWER ✔✔True
Which of the following energies are part of the total energy of a flowing
fluid? - 🧠ANSWER ✔✔Enthalpy
Kinetic energy
Potential energy
Which of the following statements are true? (Select all that apply.) -
🧠ANSWER ✔✔-the steady-flow process is a process during which a fluid
flows through a control volume and does not change with time-during a
steady flow process, boundary work is zero-the steady flow implies that the
fluid properties can change from point to point, but at any point, they
remain constant during the entire process
The volumetric flow rate of water flowing through a pipe is 5 L/s, and the
density of water is 1 kg/L. What is the mass flow rate? - 🧠ANSWER ✔✔5
kg/s
,Reason:
Mass flow rate is equal to the product of density and volumetric flow rate.
True or false: In a single-stream, steady flow system, the mass flow rates
for the inlet and outlet must be the same. - 🧠ANSWER ✔✔True
Which of the following statements are true? (Select all that apply.) -
🧠ANSWER ✔✔-The rate of change of mass within a control volume minus
the net flow rate in and plus the net flow rate out of the control surface must
equal to zero.
-In a steady flow process, the total rate of mass entering a control volume
is equal to the total rate of mass leaving it.
In an open system, when mass flows across control volume boundaries,
some work is required to push the mass into or out of the control volume,
and this is known as ______ work. - 🧠ANSWER ✔✔flow
In a steady flow process, energy can be transferred by ______. -
🧠ANSWER ✔✔work, mass, and heat
True or false: The total energy for a flowing fluid consists of an additional
term when compared with the total energy for a nonflowing fluid.
3
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
, True false question. - 🧠ANSWER ✔✔True
During a steady-flow process, the fluid properties at an inlet or exit must
______. - 🧠ANSWER ✔✔remain constant
Nozzle
matches
Choice, A device that increases the velocity of a fluid at the expense of
pressure
A device that increases the velocity of a fluid at the expense of pressure
Diffuser
matches
Choice, A device that increases the pressure of a fluid by slowing it down
A device that increases the pressure of a fluid by slowing it down -
🧠ANSWER ✔✔hi
In a single-stream, steady flow system, the mass flow rate can be defined
as the product of ___________, __________, and ___________. -
🧠ANSWER ✔✔Density, velocity, and area
Turbine - 🧠ANSWER ✔✔produces shaft work
