An Ideal gas is being heated in a circular duct as while flowing over an electric heater of 130 kW. The diameter of duct is 500 mm. The gas enters the heating section of the duct at 100 kPa and 27 deg C with a volume flow rate of 15 m3/s. If heat is lost from the gas in the duct to the surroundings at a rate of 80 kW, Calculate the exit temperature of the gas in deg C. (Assume constant pressure, ideal gas, negligible change in kinetic and potential energies and constant specific heat; Cp =1000 J/kg K; R = 500 J/kg K
Answers
Answer:
The exit temperature of the gas = 32° C
Explanation:
Solution
Given that:
Inlet temperature T₁ = 27°C ≈ 300.15 K
Inlet pressure P₁ = 100 KPa = 100 * 10^3 Pa
Volume flow rate , V = 15 m/s³
Diameter of the deduct, D = 500 mm = 0.5 m
Electric heater power, W heater = 130 kW = 130 * 10^3 W
The heat lost Q = 80 kW = 80 * 10^3 W
Now,
From the ideal gas law, density of the air at the inlet is given as :
ρ₁ = P₁/RT₁ = 100 * 10^3/500 * 300
=0.6667 kg/m³
The mass flow rate through the duct is computed below:
m = ρ₁ V = 0.6667 * 15 = 10 kg/s
Thus
Applying the first law of thermodynamics to the process is shown below:
Q + m (h₁ + V₁²/2 + gz₁) = m (h₂ + V₂²/2 + gz₂) + W (Conservation energy)
So,
If we neglect the potential and kinetic energy changes of the air, the above equation can be written again as:
Q + m (h₁) = m (h₂) + W
or
Q - W heater =m (h₂ - h₁) or Q - W heater =m (T₂ - T₁)
Thus
h₂ - h₁ = Cp T₂ - T₁
Now by method of substitution the known values are:
(- 80 *10^3) - (-130 * 10^3) = 10 * 100 * (T₂ -27)
Note: The heat transfer is taken as negative because the heat is lost by the gas and work done is also taken as negative because the work is done on the gas
So,
Solving for T₂,
T₂ = 32° C
Therefore the exit temperature of the gas = 32° C
Related Questions
How is the law of conservation of matter best represented in a chemical reaction
Answers
Answer:
Umm.... because the spit that comes up of your mouth when you talk mixes with the air
Explanation:
-0-1"
-0
-20
-15
-10
0
-5
Answers
75743366
Explanation:
b) 23.5 years + 2.6 light years
Answers
Do you think computer professionals need to have a moral code specific to their profession?
Do you think technology has created a different set of moral values?
Give an example of a specific situation where a computer code of ethics is used?
Have you ever been faced with an ethical decision involving information technology?
Answers
Computer professionals need to have a moral code specific to their profession as technology has created a different set of moral values.
This is because more than 100 years of technology and innovation have created an entirely new set of ethical concerns for computer professionals. The reason why computer professionals require a moral code is that their work often entails access to sensitive information and computing systems that, if exploited, could result in significant harm to individuals and organizations.
Technology has created a different set of moral values because it has brought about new ethical challenges that were previously unheard of. For example, online privacy, cyberbullying, identity theft, and hacking are all ethical issues that have arisen due to technology advancements.
To know more about visit:
https://brainly.com/question/7464249
#SPJ11
Select the correct answer. The most frequent maintenance task for a car is: A. Oil changes B. Tire replacements C. Coolant changes D. Brake replacements
Answers
Answer:
A. Oil changes
Explanation:
It depends on the car and its usage and environment. Usually oil is supposed to be changed every few months, more often if the car is driven a lot. Coolant changes may be indicated as seasons change, so will generally occur less frequently than oil changes.
Tire and brake replacement depend on usage and driving habits. Some owners may never have to replace either one, if they trade their car every year or two. Folks who drive with their foot on the brake pedal may have to replace brakes relatively often.
The most frequent task is generally oil changes.
Answer:
A. Oil changesthe most frequent maintenance task for a carIn a cout statement, which of the following will advance the output position to the beginning of the next line?
A) endl or \n
B) end1 or /n
C) \n or \t
D) \t or \b
E) \\ or \'
Answers
When a cout statement is executed, which of the following will advance the output position to the beginning of the next line?endl or \n will advance the output position to the beginning of the next line, So the correct answer is A) endl or \n.
Explanation: This statement advances the output position to the beginning of the next line.endl is the equivalent of writing "\n" and is used to move the cursor or output position to the beginning of the next line. A standard stream of output that accepts values and inserts them into the output or displays them on the screen is called the "cout" (pronounced "see-out") function. The output stream is an instance of the ostream class. The << (output) operator and the cout function are used to display results in a C++ program, and they all use the ostream class. The endl or \n options, according to the C++ standard, indicate a newline character. As a result, when a cout statement is executed, both of these characters will advance the output position to the beginning of the next line.So the correct answer is A) endl or \n.
More On Cout Statement: https://brainly.com/question/15712417
#SPJ11
The acceleration of a particle is defined by the relation a = -k/x . It has been experimentally determined that v = 15 ft/s when x = 0.6 ft and that v = 9 ft/s when x = 1.2 ft. determine (a) the velocity of the particle when x = 1.5 ft and (b) the position of the particle at which its velocity is zero.
I get the expression 1/2v^2 = -kln(x) +C and I do not know how to solve for both unknowns K and C. Solving for V is doable, but the two equations for V and X i can see how to relate. thank you. please give a hint, not full answer.
Answers
Remember that ln(x) represents the natural logarithm of x
Start by plugging in the first data point (v = 15 ft/s, x = 0.6 ft) into the equation 1/2v^2 = -kln(x) + C. Then, plug in the second data point (v = 9 ft/s, x = 1.2 ft) into the equation.
To solve for the unknowns k and C in the equation 1/2v^2 = -kln(x) + C, you can use the given experimental data to create a system of equations.
The two known data points (v = 15 ft/s when x = 0.6 ft and v = 9 ft/s when x = 1.2 ft) can be plugged into the equation to create two equations.
Start by plugging in the first data point (v = 15 ft/s, x = 0.6 ft) into the equation 1/2v^2 = -kln(x) + C. Then, plug in the second data point (v = 9 ft/s, x = 1.2 ft) into the equation. This will give you a system of two equations with two unknowns (k and C). From there, you can solve the system of equations to find the values of k and C.
Remember that ln(x) represents the natural logarithm of x.
Know more about natural logarithm here:
https://brainly.com/question/29154694
#SPJ11
Heat air rises, cools then falls. Air near heat is replaced by cooler air and the cycle repeats
Answers
all very good airmen do bench tests. (True or False)
Answers
False.
The statement "all very good airmen do bench tests".
Bench tests are designed to evaluate an airman's technical knowledge and ability to perform specific tasks, often in a simulated or controlled environment. However, there are many other factors that contribute to being a "very good" airman, such as communication skills, teamwork, leadership, and adaptability. Furthermore, not all airmen have the same job responsibilities or technical requirements. Airmen who work in administrative or support roles may not require the same level of technical expertise as those who work directly with aircraft or other complex equipment. While bench tests can be an important tool for assessing an airman's technical abilities, they are not the only factor that determines whether someone is a "very good" airman. The qualities and skills that make an airman successful can vary depending on their job responsibilities and the specific needs of their unit or organization.For such more questions on bench tests
https://brainly.com/question/15724895
#SPJ11
Tech A says that electromotive force is also known as voltage. Tech B says that when electrons flow in
one direction only, this is DC. Who is correct?
ту
O Tech A
O Tech B
O Both A and B
Neither A nor B
Answers
Answer:
neither
Explanation:
yeah
relays are electromechanical switches that lack auxiliary contacts. true or false
Answers
A relay is an electrical device that is used to switch one electrical circuit on and off by the use of another electrical circuit.
When an electric current flows through the coil inside the relay, it generates a magnetic field. This magnetic field then activates a switch, which allows the current to flow through a different circuit.Relay contacts are used to connect or disconnect a device or signal in a relay circuit. Relay contacts can be either normally open (NO) or normally closed (NC). While NC contacts are used to provide a path to ground when the relay is not activated, NO contacts are used to break a circuit when the relay is activated.Auxiliary contacts on relays are additional contacts that are not part of the main switching mechanism. These contacts can be used for a variety of purposes, such as indicating the status of the relay or providing additional switching functionality.
So, the given statement "relays are electromechanical switches that lack auxiliary contacts" is false. A relay is an electrical device that uses electromagnetism to switch one electrical circuit on and off by the use of another electrical circuit. Relay contacts can be either normally open (NO) or normally closed (NC), and auxiliary contacts are additional contacts that are not part of the main switching mechanism.
Learn more about magnetic field here:
brainly.com/question/14848188
#SPJ11
Two stepped bar is supported at both ends.At the join point of two segments,the force F is applied(downwards).Calculate reactive forces R1 and R3 at the supports.What is value of absolute maximal stress?
Choose one answer nearest your result.
given= d1=10mm d2=20mm L1=20mm L2=10mm E=200GPa F=20kN
Answers
Answer:
F=200kN
Explanation:
Describing Tasks for Stationary Engineers Click this link to view O*NET’s Tasks section for Stationary Engineers. Note that common tasks are listed toward the top, and less common tasks are listed toward the bottom. According to O*NET, what are common tasks performed by Stationary Engineers? Check all that apply. observing and interpreting readings on gauges, meters, and charts managing financial resources to order supplies and equipment writing computer programs to control equipment testing boiler water quality or arranging for testing creating safety regulations after experimentation operating or tending stationary engines, boilers, and auxiliary equipment
Answers
Answer:
A, D, F
Explanation:
took on edge.
Answer:
The answer is A,D,F
A:observing and interpreting readings on gauges, meters, and charts
D:testing boiler water quality or arranging for testing
F:operating or tending stationary engines, boilers, and auxiliary equipment
Explanation:
I got all right on edge.
A shaft of a circular cross section is supported by two housings at B and C. The shaft
is subjected to static loads: concentrated force N applied by gear D and an applied torque T. The yielding strength of the shaft is Sy, and the diameter of the shaft is d. For circular cross sections, | = nd*/64, J = md*/32. The length of the shaft is L. Transverse shear stress is ignored here.
1) Draw the bending moment diagram of the shaft. Specify the location of the weakest (most dangerous) cross section A on bending moment diagram.
2) Draw the weakest point(s) on cross section A.
3) Determine the von-Mises stress at the weakest point(s).
4) Determine the factor of safety n based on Distortion Energy Theory.
Answers
Answer:
1) The bending moment diagram of the shaft is shown in Figure 1. The weakest cross section A is located at the point where the bending moment is maximum.
2) The weakest point on cross section A is located at the point where the bending moment is maximum.
3) The von-Mises stress at the weakest point is given by:
σ = M/I
where M is the bending moment and I is the moment of inertia of the cross section.
4) The factor of safety n is given by:
n = Sy/σ
where Sy is the yield strength of the shaft and σ is the von-Mises stress at the weakest point.
Explanation:
Hope this helps!
Convenience items like liquid egg are a lot more expensive?
True
Or False
Answers
Answer:
True
Explanation:
It's just because of the processing
what is the dimensions of beta
Answers
Answer:
byee byee bbbbbbbbbbbb
HELP! It’s for an architecture class on PLATO
Select the correct answer.
Which association maintains the International Building Code?
A. NFPA
B. ICC
C. EPA
D. DOJ
Answers
Answer:
ICC
Explanation:
The International Building Code (IBC) is a model building code developed by the International Code Council (ICC). It has been adopted for use as a base code standard by most jurisdictions in the United States.
A trash incinerator has an effective stack height of 100m. On a sunny day with a 2m/s wind speed the concentration of sulfur dioxide 200m directly downwind is measured at 5.0 x10^-5 g/m^3. Estimate the mass release rate in g/s off sulfur dioxide from the stack. Also estimate the maximum sulfur dioxide concentration expected on the ground and its location downwind from the stack.
Answers
The estimated mass release rate of sulfur dioxide from the stack is [insert value] g/s. The maximum sulfur dioxide concentration on the ground is expected to be [insert value] g/m^3, and its location downwind from the stack is [insert distance].
To estimate the mass release rate of sulfur dioxide from the stack, we need to consider the concentration measured at a specific distance downwind from the stack and the wind speed. In this case, the concentration of sulfur dioxide measured at a distance of 200m downwind is 5.0 x 10^-5 g/m^3. To calculate the mass release rate, we can use the formula:
Mass release rate = Concentration x Cross-sectional area x Wind speed
The effective stack height of the trash incinerator is given as 100m, and we can assume a circular cross-section for the stack. By substituting the given values, we can calculate the mass release rate.
To estimate the maximum sulfur dioxide concentration on the ground, we need to consider the dispersion of pollutants in the atmosphere. The concentration of pollutants decreases as the distance from the source increases. The maximum concentration is usually expected to occur near the source and decreases with distance.
The exact calculation for the maximum concentration and its location downwind from the stack involves complex atmospheric dispersion models. These models consider various factors such as wind speed, atmospheric stability, and topography. Without additional information, it is challenging to provide an accurate estimation of the maximum concentration and its location in this scenario.
Learn more about Mass release rate here :
https://brainly.com/question/31736034
#SPJ11
The phase angle in a circuit is 45 degrees what's the power factor of this circuit?
Answers
The power factor of the circuit is 0.7071
What is Power factor?Power factor (PF) is the ratio of working power, measured in kilowatts (kW), to apparent power, measured in kilovolt amperes (kVA). Apparent power, also known as demand, is the measure of the amount of power used to run machinery and equipment during a certain period. It is found by multiplying (kVA = V x A). The result is expressed as kVA units.
Power factor is expressed as the cosine of the phase angle.
The phase angle is given as 45°
Therefore the power factor in the circuit is cos45° = 0.7071
learn more about power factor from
https://brainly.com/question/25543272
#SPJ1
QUESTIONS
DOK S STANDARD RST.1
MS-PS2-2
A car driving at a constant speed of 20 m/s(meters per second)
turns right, down a street.
1. Is the car accelerating during the turn? Why or why not?
2. Would you feel any of the movement during this event? Why
or why not?
Answers
ANSWER:
1) The car is not accelerating, because for the the car to turn while accelerating down the street, it has to deaccelerate (reduce speed) due to CENTRIPETAL FORCE that is acting on the car during the turn. This force acts to bring the car in the direction where it has turned to.
2) You will feel the movement as everyone in the car will tend to fall to the left, while the car makes a right turn. This is because of CENTRIFUGAL FORCE, which is acting to take the car to a left direction, while the car is turning to the right direction.
the three most common and well-known industry regulatory agencies are all a part of the council of better business bureaus and help _______________________.
Answers
The three most common and well-known industry regulatory agencies are all a part of the Council of Better Business Bureaus and help ensure consumer protection and business integrity.
The Council of Better Business Bureaus (BBB) is an organization that promotes ethical business practices and consumer trust in the marketplace. It consists of several industry regulatory agencies that play a crucial role in safeguarding consumer interests and maintaining fair business practices. The three most common and well-known regulatory agencies associated with the BBB are:
Federal Trade Commission (FTC): The FTC is a federal agency that enforces consumer protection laws, prevents fraudulent and deceptive business practices, and promotes fair competition in the marketplace. It investigates and takes legal action against companies that engage in unfair or deceptive practices, ensuring consumer rights are protected.
Consumer Financial Protection Bureau (CFPB): The CFPB is responsible for regulating financial products and services, ensuring that consumers are treated fairly by banks, lenders, and other financial institutions. It enforces laws related to consumer financial protection, such as those governing mortgages, credit cards, and student loans.
Federal Communications Commission (FCC): The FCC is an independent agency that regulates communication and media services in the United States. It oversees areas such as internet access, broadcasting, wireless communications, and telecommunications. The FCC protects consumer interests by enforcing rules related to consumer privacy, telemarketing, and unsolicited communications.
Know more about Better Business Bureaus here;
https://brainly.com/question/4166921
#SPJ11
What lives at layer 3 (the network layer) of the OSI model?
Answers
Layer 3 of the OSI (Open Systems Interconnection) model, known as the network layer, is responsible for providing end-to-end communication between hosts in different networks.
The network layer is responsible for routing and forwarding data packets across different networks, as well as handling addressing and logical connectivity.
The main entities that live at layer 3 (the network layer) of the OSI model include:
Routers: Routers are network devices that operate at the network layer and are responsible for forwarding data packets between different networks. They use routing tables and protocols to determine the best path for data packets to reach their destination across multiple networks.
IP (Internet Protocol): IP is a network layer protocol that provides logical addressing and routing functionality. It is responsible for assigning unique IP addresses to devices on a network, and for routing data packets based on those IP addresses.
ICMP (Internet Control Message Protocol): ICMP is a network layer protocol that is used for sending error messages and operational information about network conditions. It is often used for diagnostic purposes, such as ping and traceroute, to check the connectivity and status of network devices.
Network Addressing: Layer 3 is also responsible for assigning and managing IP addresses, which are used to uniquely identify devices on a network.
Subnetting and VLANs: Layer 3 may also involve subnetting and VLANs (Virtual Local Area Networks), which are used for network segmentation and management to improve efficiency and security.
In summary, layer 3 of the OSI model includes routers, IP, ICMP, network addressing, and other protocols and technologies that are responsible for routing, addressing, and logical connectivity in a network.
learn more about OSI here:
https://brainly.com/question/25404565
#SPJ11
Answer the following either true (T) or false (F) (5 pts)
A geotechnical engineer made a preliminary settlement analysis for a foundation of an office building that is to be constructed at a location where the soil strata contain a compressible clay layer. She calculated 50 mm of primary consolidation settlement. The building will impose an average vertical stress of 150 kPa in the clay layer. As often happens in design practice, design changes are required. In this case, the actual thickness of the clay is 30% more than the original soil profile indicated. The estimated new primary consolidation settlement will also be 30% more and equal to 65 mm.
A foundation with an inclined load will tend to have a smaller bearing capacity than the same foundation with a vertical load.
Secondary settlement of a foundation is caused by a constant applied stress.
Consolidation can be defined as the reduction in soil volume due to the expulsion of water following loading.
Dense sand and undrained clay soils tend to experience punching shear failure.
Answers
Answer:
1. True
2. True
3. False
Explanation:
The office location is where the soil layer is not uniform. The thickness of the soil varies which could lead to doors being jammed. The engineer needs to estimate the differential in clay soil.
The inclined surface can hold less weight than a vertical surface. The capacity to hold the weight is due to the gravitational force which is exerted to the load.
WHICH TASK BEST FITS THE ROLE OF A DESIGN ENGINEER ?
Answers
Answer: drafting blueprints
Explanation:
Where would an engineer indicate the unit of measurement used in a design
Answers
An engineer would indicate the unit of measurement used in a design in millimeters.
What are measurements?The primary unit of measurement is the stocking unit of measure for a given item in a specific organization. You must define an item attribute that serves as the primary unit of measurement when creating each item.
Because the technical drawings are scaled, engineers, architects, and builders may create the items according to exact specifications.
When understanding scales, the number on the left relates to the measurement of the drawing, while the number on the right represents the actual size of the object.
Therefore, a millimeter is used in a design.
To learn more about measurements, refer to the link:
https://brainly.com/question/28390923
#SPJ1
What are the indications that Cece is having problems
with her computer hardware? Check all that apply
-losing the Internet connection
-waiting for five minutes
-computer going blank
-mouse pointer freezing
-keyboard getting stuck
Answers
Answer:
-Computer going blank .
-Mouse pointer freezing.
-Keyboard getting stuck.
Explanation:
Any problems with the computer related to its hardware will consist of issues directly related to the physical components of the PC or computer. So any problem involving the physical component of the computer, then it can be termed as a hardware problem.
Based on the problems given in the option, the hardware issues will be problems with the computer, mouse, and keyboard. These form the physical parts of the computer so they will be a hardware issue.
Thus, the correct answers are the third, fourth, and fifth options.
Answer:
c d e
Explanation:
Can you find thevenin equivalent for this example?
Answers
With the load impedance open-circuited, the Thevenin voltage is calculated. Find the voltage at the load terminals that is open-circuit.
Explaining Thevenin's TheoremThevenin's Theorem: What is it? According to Thevenin's Theorem, any linear circuit can be made simpler by using a single dc voltage and a series resistance, regardless of how complex it is.
What are Thevenin's theorem's benefits?It makes the less crucial section of the circuit simpler and makes it possible for us to see the output part's operation in real time. It simplifies a complicated circuit by putting one emf source in series with one resistance.
To know more about Thevenin's Theorem visit:
https://brainly.com/question/28007778
#SPJ1
Water enters a centrifugal pump axially at atmospheric pressure at a rate of 0.12 m3
/s and at a
velocity of 7 m/s, and leaves in the normal direction along the pump casing, as shown in Figure.
Determine the force acting on the shaft (which is
also the force acting on the bearing of the shaft) in
the axial direction.
Answers
Answer:
Water enters a centrifugal pump axially at atmospheric pressure at a rate of 0.12 m3/s and at a velocity of 7 m/s, and leaves in the normal direction along the pump casing, as shown in Fig. PI3-39. Determine the force acting on the shaft (which is also the force acting on the bearing of the shaft) in the axial direction.
Step-by-step solution:
Step 1 of 5
Given data:-
The velocity of water is .
The water flow rate is.
The DOT places more restrictions on operators of heavy trucks than on lighter trucks. Why do you think this is?
Only the states can regulate drivers of light trucks.
The drivers of heavy trucks go on long hauls, and therefore are most likely to engage in smuggling and related activities that might pose a national security risk.
The DOT does not actually place more restrictions on operators of heavy trucks.
The DOT is tasked with protecting the safety of people on the roadways, and long hauls pose more such risks.
Answers
The DOT places more restrictions on operators of heavy trucks than on lighter trucks. The reason for this is that "The DOT is tasked with protecting the safety of people on the roadways, and long hauls pose more such risks."
What is the DOT?The United States Department of Transportation (or DOT) is a federal cabinet department of the United States government involved with transportation. It was founded in 1966 and went into operation on April 1, 1967. The United States Secretary of Transportation is in charge of it.
Its goal statement is: "To serve the United States by assuring a rapid, safe, efficient, open, and convenient transportation system that satisfies our essential national interests and improves the quality of life of the American people today and in the future."
Learn more about DOT:
https://brainly.com/question/14329984
#SPJ1
The Republican National Committee publishes a monthly digest of information for Republicans called .
Answers
Answer: The Republican
Explanation: