Solution :
Given :
Dry bulb temperature, T = 30 degree C
Absolute pressure, P = 102 kPa
Partial pressure of water vapor, [tex]$P_v$[/tex] = 1.5 kPa
a). Relative humidity is given by
[tex]$\phi = \frac{P_v}{P_{sat}}$[/tex]
At T = 30 degree C, from the steam table, we have saturation temperature as 4.2469 kPa.
[tex]$\phi = \frac{1.5}{4.2469}$[/tex]
= 0.35319
= 35.31 %
b). Humidity ratio,
[tex]$w= 0.622 \times \frac{P_v}{P-P_v}$[/tex]
[tex]$w= 0.622 \times \frac{1.5}{102-1.5}$[/tex]
w = 0.009283 kg per kg of dry air
c). Dew point temperature is the saturation temperature at vapor pressure of air (can be found from steam table)
At [tex]$P_v$[/tex] = 1.5 kPa, saturation temperature = 1.02 degree C
∴ Dew point temperature = 13.02 °C
d). Humidity ratio can be be defined as the ratio of mass of water vapor to the mass of dry air.
i.e. [tex]$w=\frac{m_v}{m_a}$[/tex]
[tex]$0.009283 =\frac{10}{m_a}$[/tex]
∴ [tex]m_{a}[/tex] = 1077.170 kg of dry air
Calculate the reflection loss that is incident normal to the surface of a triple pane window (assume n for window glass is 1.5)
Answer: the reflection loss is 4%
Explanation:
Given that;
n for window glass is 1.5
we know that
Reflection Loss rλ = (nλ - 1)² / (nλ + 1)²
the reflection of loss rλ at normal incidence between two media with different refractive indexes rλ = n'/n, the ratio indices
where n is index of refraction of air ( 1 )
and n' is the refraction of window glass ( 1.5 )
our nλ is 1.5
so we substitute into the equation
rλ =[ (1.5 - 1)² / (1.5 + 1)²] × 100
= [0.25 / 6.25] × 100
= 0.04 × 100
= 4%
Therefore the reflection loss is 4%
What is the output? for num in range(3): print (num + 5)
Answer: 5 6 7
Explanation:
you can run this in python and get this result
The output for the given program is: 5 6 7
What is Python Programming Language?This refers to the high-level language that was created and is used for data structures due to its OOP (object-oriented programming).
Hence, this python code asks for an array of numbers in the range of 3 and when that is found, it should make a display of the number and increment it.
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A fan draws air from the atmosphere through a 0.30-mdiameter round duct that has a smoothly rounded entrance. A differential manometer connected to an opening in the wall of the duct shows a vacuum pressure of 2.5 cm of water. The density of air is 1.22 kg/m3 . Determine the volume rate of air ow in the duct in cubic feet per second. What is the horsepower output of the fan?
Answer:
V = 50 ft³/s
H.P = 0.466
Explanation:
Given that
Diameter of the duct, D = 0.3 m
Vacuum Pressure of the duct, Z = 0.025 m
P(w) = pressure of water, 1000 kg/m³
P(a) = pressure of air, 1.22 kg/m³
To find the pressure change we use the formula
ΔP = P(w) * g * Z
ΔP = 1000 * 9.8 * 0.025
ΔP = 245 Pa.
We need the area, do we find that too
A = πd²/4
A = π * 0.3² * 1/4
A = 0.071 m²
Recall the energy equation to be
1/2v² = ΔP/p(a) , so that if we rearrange, we have
v² = 2ΔP/p(a)
v = √(2ΔP/p(a)), on substituting the values, we have
v = √(2 * 245)/1.22
v = √490/1.22
v = √401.64
v = 20.04
The volume flow rate is then equal to
Velocity * Area.
V = 20.04 * 0.071
V = 1.42 m³/s, converting to ft³/s, we have 50 ft³/s
Horsepower output is gotten using
P = ΔP * V
P = 245 * 1.42
P = 347.9 w, converting this to HP, we have 0.466 HP
A cyclist is turning the pedals of his bicycle at a speed of 60RPM while exerting a torque of 1 lb-ft. The input sprocket has 40 teeth. What is the number of teeth on the output sprocket, if the driven wheel is rotating at 240 RPM?
Answer:
10
Explanation:
The speed of the chain is the same for both sprockets.
vᵢ = vₒ
ωᵢ rᵢ = ωₒ rₒ
The sprockets have the same pitch, so the radius is proportional to the number of teeth. So we can say:
ωᵢ nᵢ = ωₒ nₒ
Plugging in values:
(60 rpm) (40) = (240 rpm) nₒ
nₒ = 10
The output sprocket has 10 teeth. This makes sense, if the output sprocket is 4 times smaller, it will turn 4 times faster than the input sprocket.
Answer: it is 10 teeth and the guy under me already explained soo
Explanation:
What is one step taken when solving a computer software problem? making sure the power cord is plugged in properly scanning the computer and deleting any viruses searching for any spills or damage to the computer taking a look at all the cables and connectors when students have computer trouble they usually are expected to make any simple fixes on their own. solve complex issues by themselves. drop their school work until it is resolved. pay a technician a high fee to fix the issue.
Answer:
Answer: B) Scanning the computer and deleting any viruses.
Explanation:
Some of the feedback I hear from new developers working on a programming problem revolves around uncertainty of where to start. You understand the problem, the logic, basics of the syntax, etc. If you see someone else’s code or have someone to guide you, you can follow along. But maybe you feel uncertain about doing it yourself and have trouble turning your thoughts into code at first even though you understand the syntax or logic. Here’s my process and some tips to tackling a sample problem that hopefully some of you may find helpful in your journey.
If you need further expenation then:
Some of the feedback I hear from new developers working on a programming problem revolves around uncertainty of where to start. You understand the problem, the logic, basics of the syntax, etc. If you see someone else’s code or have someone to guide you, you can follow along. But maybe you feel uncertain about doing it yourself and have trouble turning your thoughts into code at first even though you understand the syntax or logic. Here’s my process and some tips to tackling a sample problem that hopefully some of you may find helpful in your journey.
May i please have brainliest
Answer:
B. scanning the computer and deleting any viruses
Explanation:
I took the test on edge, and this makes most sense to me. Good luck:)
which term describes how a mineral looks when it breaks apart in an irregular way
Answer:
Fracture.
Explanation:
Fracture describes how a mineral looks when it breaks apart in an irregular way.
Answer:
Fracture.
Explanation:Fracture describes how a mineral looks when it breaks apart in an irregular way.
A spur gearset has a module of 6 mm and a velocity ratio of 4. The pinion has 16 teeth. Find the number of teeth on the driven gear, the pitch diameters, and the theoretical center-to-center distance
Answer:
NG=64 teeth
dG=384mm
dP=96mm
C=240mm
Explanation:
step one:
given data
module m=6mm
velocity ratio VR=4
number of teeth of pinion Np=16
Step two:
Required
1. Number of teeth on the driven gear
[tex]N_G=N_P*V_R\\\\N_G=16*4\\\\N_G=64[/tex]
The driven gear has 64 teeth
2. The pitch diameters
The driven gear diameter
[tex]d_G=N_G*m\\\\d_G=64*6\\\\d_G=384[/tex]
The driven gear diameter is 384mm
The pinion diameter
[tex]d_P=N_P*m\\\\d_P=16*6\\\\d_P=96[/tex]
Pinion diameter is 96mm
3. Theoretical center-to-center distance
[tex]C=\frac{d_G+d_P}{2} \\\\C=\frac{384+96}{2} \\\\C=\frac{480}{2}\\\\C=240[/tex]
The theoretical center-to-center distance is 240mm
The results are listed below:
The driven gear has 64 teeth.The pinion has a diameter of 96 millimeters and the driven gear has a diameter of 384 millimeters.The theoretical center-to-center distance is 240 millimeters.First, we proceed to find the number of teeth of each gear ([tex]N_{D}, N_{P}[/tex]) based on the fact that gear only fit when they have the same module ([tex]m[/tex]). The velocity ratio ([tex]r_{v}[/tex]) is defined by the following relationship:
[tex]r_{v} = \frac{N_{D}}{N_{P}}[/tex] (1)
If we know that [tex]r_{v} = 4[/tex] and [tex]N_{P} = 16[/tex], then the number of teeth of the driven gear is:
[tex]N_{D} = r_{v}\cdot N_{P}[/tex]
[tex]N_{D} = 4\cdot (16)[/tex]
[tex]N_{D} = 64[/tex]
The driven gear has 64 teeth.
The pitch diameter ([tex]D[/tex]) is obtained by multiplying the number of teeth ([tex]N[/tex]) by module ([tex]m[/tex]), in milimeters.
Pinion
[tex]D_{P} = m\cdot N_{P}[/tex] (2)
([tex]m = 6\,mm[/tex], [tex]N_{P} = 16[/tex])
[tex]D_{P} = (6\,mm)\cdot (16)[/tex]
[tex]D_{P} = 96\,mm[/tex]
Driven gear
[tex]D_{D} = m\cdot N_{D}[/tex] (3)
([tex]m = 6\,mm[/tex], [tex]N_{D} = 64[/tex])
[tex]D_{D} = (6\,mm)\cdot (64)[/tex]
[tex]D_{D} = 384\,mm[/tex]
The pinion has a diameter of 96 millimeters and the driven gear has a diameter of 384 millimeters.
Lastly, the theoretical center-to-center distance is calculated by the following formula:
[tex]d = \frac{1}{2}\cdot (D_{P}+D_{D})[/tex] (4)
([tex]D_{P} = 96\,mm[/tex], [tex]D_{D} = 384\,mm[/tex])
[tex]d = \frac{1}{2}\cdot (96\,mm + 384\,mm)[/tex]
[tex]d = 240\,mm[/tex]
The theoretical center-to-center distance is 240 millimeters.
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25points and brainliest if correct A, B, C, D
Which option distinguishes the most appropriate action to take next in the following scenario?
Lisa is a new worker on a farm. She needs to access an area of the farm at the top of the hill on a tractor. She tries backing the tractor up the slant and finds that it will not make the ascent.
A. Lisa should drive across the hill at an angle to get to the top.
B. Lisa should reach the top of the hill by finding a less steep path.
C. Lisa should drive forward up the hill at a slow pace to get to the top.
D. Lisa should reach the top of the hill by finding a more experienced driver.
Answer:A
Explanation:
B - it never talked about a steep path or not.
C- it never stated the speed.
d- more experienced driver makes a little bit of sence since she is new but she is new at the farm not driving.
thats my guess.
Answer:
b is the answer
Explanation:
Ignoring reflection at the air-soil boundary, if the amplitude of a 3-GHz incident wave is 10 V/rn at the surface of a wet soil medium, at what depth will it be down to 1 mV/m? Wet soil is characterized by µr = 1, εr = 9, and σ = 5 × 10–4S/m.
Answer:
5 multiply by 10 S/M
Based on the calculations, the incident wave would be down to 1 mV/m at a depth of 287.82 meters.
How to calculate the depth of the wet soil medium.Since the medium is a wet soil, it is characterized by the following:
Dielectric constant, µr = 1.Relative permitivitty, εr = 9.Electrical conductivity, σ = 5 × 10⁻⁴ S/m.Next, we would determine loss tangent, so as to know if the wet soil is a low-loss medium:
For a low-loss medium; ε''/ε' = σ/ωε < 0.01.
[tex]\frac{\sigma}{\omega \epsilon} = \frac{5 \times 10^{-4} \;\times\; 36 \pi}{2\pi \;\times \;3 \times 10^9\; \times\; 10^{-9} \times \;9} \\\\\frac{\sigma}{\omega \epsilon} =3.32 \times 10^{-4}[/tex]
Therefore, the wet soil medium is a low-loss dielectric and its absorption (attenuation) coefficient is calculated by using this formula:
Note:
[tex]\alpha = \frac{\sigma}{2}\sqrt{\frac{\mu}{\epsilon}} \\\\\alpha = \frac{\sigma}{2} \times \frac{120\pi}{\sqrt{\epsilon_r} } \\\\\alpha =\frac{5 \times 10^{-4} \times 120\pi}{2 \times \sqrt{9} } \\\\[/tex]
α = 0.032 Np/m.
Now, we calculate the depth:
[tex]E(z) = E_oe^{-\alpha z} = 10e^{-\alpha z}\\\\10^{-3}=10e^{-0.032 z}\\\\ln(10^{-4})=-0.032 z\\\\-9.21 \times 10^9=-0.032z\\\\z=\frac{-92.1 0}{-0.032}[/tex]
z = 287.82 meters.
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When your workplace obtains new materials, you should add them to the chemical list:
Answer:
immediately
Explanation:
The beam below will be subjected to a live load of 600 lb/ft, a concentrated live load of 25 kip, and a dead load of 300 lb/ft. a) What is the maximum positive moment that can be produced at G? b) What is the maximum negative moment that can be produced at G?
Answer:
hello some part of your question is missing below is the complete question
answer :
A) 162750 Ib.ft
B) - 64950 Ib.ft
Explanation:
Applying Muller-Breslau's law
we will make assumptions which include assuming an imaginary hinge at G
therefore the height of I.LD for B.M at G = ( 12 * 8 ) / 20 = 4.8
height of I.L.D at C = 2.4 ( calculated )
height of I.L.D at F = 1.5 ( calculated )
A) Determine Maximum positive moment produced at G
[tex]M ^+[/tex] = [ (1/2 * 20 * 4.8 ) ( 600 + 300 ) ] + [ ( 25 * 4.8 * 10^3 ) ] - [ ( 1/2 *2.4*20 ) * 300 ] + [ (1/2 * 1.5 * 10 ) ( 600 + 300 ) ]
= 162750 Ib.ft
B) Determine the maximum negative moment produced at G
[tex]M ^-[/tex] = [ ( 1/2 * 20 * 4.8 ) * 300 ] - [ ( 1/2 * 2.4 * 20 ) ( 600 + 300 ) ] - [ (2.5 * 10^3 * 2.4 ) ] + [ ( 1/2 * 1.5 * 10) * 300 ]
= - 64950 Ib.ft
A ________ is a condition or capability needed by a user to solve a problem or achieve an objective that satisfies a standard or specification or any other formally documented need.
What do engineers spend up to 25 percent of their design process formulating and analyzing?
the team that will work on the project
if a material is malleable
if a design will need a functional or superficial improvement
the perfect material for their design
Answer:
Engineers spend up to 25 percent of their design process formulating and analyzing
the team that will work on the project.
Explanation:
During the design engineering stage of a project, the team is a very important decision item because determining the required team also determines the cost and the technical skill requirements of the project. The cost depends, to a large extent, on the technical skills of those that will work on the project. When the technical skill requirements are not met, the project will be massively jeopardized.
Answer:
the team that will work on the project.
Explanation:
Which of the following is used to estimate the size of a room?
A) Drop ceilings
B) Window frames
C) Bricks
D) Room trim
Answer:
I think the answer is drop ceilings
Explanation:
Calculate the cost per cubic yard to place concrete using each of the alternatives described. The work in both cases consists of placing 140 cubic yards of concrete in footings.
a. Using a crane and bucket at a price of $225 per hour, including an operator, with a crew consisting of 6 laborers, a cement finisher, and a foreman. The concrete will be placed in 7 hours using this setup, and transportation of the crane costs $390.
b. Using a concrete pump at a price of $295 per hour, including an operator and a crew consisting of 5 laborers, a cement finisher, and a foreman. With this setup, concrete is placed in 6 hours and transportation of the pump costs $290.
Answer:
Cost per cubic yard to place concrete using each of the following alternatives:
Alternative a = $14.04
Alternative b = $14.71
Explanation:
a) Data and Calculations:
Work of concrete in footings = 140 cubic yards
a. Price of using crane and bucket = $225 per hour
Number of hours required for this setup = 7 hours
Transportation of the crane = $390
Therefore, total cost under this alternative = $1,965 (($225*7) + $390)
Cost per cubic yard = $14.04 ($1,965/140)
b. Price of using a concrete pump = $295 per hour
Number of hours required for this setup = 6 hours
Transportation of the pump = $290
Therefore, total cost under this alternative = $2,060 (($295*6) + $290)
Cost per cubic yard = $14.71 ($2,060/140)
A 1-in (internal diameter) pipe is used to supply water to a low-pressure tank with an MAWP of 20 psig. The water is supplied through a regulator from a source with a maximum pressure of 100 psig. Determine the diameter of a conventional spring-operated relief required to protect the vessel from a regulator failure. Be sure to state clearly any assumptions and your justifications for them.
Answer:
3.4 inches
Explanation:
Determine the diameter required to protect the vessel from a regulator failure ( relief diameter )
A = [tex]\frac{\pi d^2}{4}[/tex]
Hence d = [tex]\sqrt{\frac{4A}{\pi } }[/tex] = [tex]\sqrt{\frac{4 * 9.08}{\pi } }[/tex] = 3.4 inches
attached below is the remaining part of the solution
20 points and brainliest is it A, B, C, D
Which of the following OSHA colors would you expect to find around material that is awaiting repair?
A. red
B. blue
C. green
D. yellow
Answer:
I think is B
Explanation:
A 18-ft thick clay layer in the field (drained on one side) is normally consolidated. When the pressure is increase from 0.75 ton/ft^2 to 1.5 ton/ft^2, the void ratio decreases from 1.12 to 0.98. The hydraulic conductivity, k, of the clay during the above loading range was found to be 4.3 times 10^-7 cm/sec. a. How long (in days) will it take for the clay layer to reach 70% reach 70% consolidation? b. What is the settlement at that time (that is, at 70% consolidation)?
Answer:
a) 294.34 days
b) Δh = 25.361 cm
Explanation:
Given data:
Thickness of clay layer = 18 ft
initial pressure = 0.75 ton/ft^2
final pressure = 1.5 ton/ft^2
Δp = 0.75 ton/ft^2
eo = 1.12
e1 = 0.98
k = 4.3 * 10^-7 cm/sec
A ) determine how long it will take to reach 70% consolidation
attached below is the detailed solution
T( time in days ) = 294.34 days
B) determine settlement at 70%
attached below is the detailed solution
Δh = 25.361 cm
A car is driven over a curb twice—once very slowly and once quite rapidly. What would you need to know about the car in the second case that you did not need to know in the first case if you were required to find the tire force that resulted from going over the curb?
Answer:
You'd need to know things like the weight of the car, the spring constant of the suspension springs.
Explanation:
Driving over the curb slowly does not have much of an "impact" because of the small potential energy it has but to find the force that results from going over the curb at a much higher speed, you would need to know the weight of the car since it directly impact the force that it applies. You also would need to know about the car's suspension, the spring material, how stiff the springs are and their spring constant to calculate the force they absorb.
I hope this answer helps.
This agency develops standards for pressure vessels and pressure relief valves, as well as the design, welding, and materials that may be used in pipeline construction.
Select one:
a. American Petroleum Institute
b. American Society of Mechanical Engineers
c. American Gas Association
d. National Fire Protection Association
Answer:
b. American Society of Mechanical Engineers
Explanation:
The "American Society of Mechanical Engineers" (ASME) is an organization that ensures the development of engineering fields. It is an accreditation organization that ensures parties will comply to the ASME Boiler and Pressure Vessel Code or BPVC.
The BPVC is a standard being followed by ASME in order to regulate the different pressure vessels and valves. Such standard prevents boiler explosion incidents.
Determine the complex power, apparent power, average power absorbed, reactive power, and power factor (including whether it is leading or lagging) for a load circuit whose voltage and current at its input terminals are given by:
a. v(t)= 100cos(377t - 30°) V
i(t)= 2.5cos(377t- 60°) A
b. Vrms= 110e^j60 , Irms= 3e^j45 A
Answer:
A) complex power = apparent power = ( 108.253 + 62.5 i ) VA
active power = 108.25 watts
reactive power = 62.5 VAR'S
power factor = cos ∅ = cos 30° = 0.866 ( lagging )
also ; current lags voltage by 30°
B) your question is not well written hence no answer
Explanation:
A) v(t) = 100 cos (377t - 30° ) v
Vrms = [tex]\frac{100}{\sqrt{2} }[/tex] ∠ -30°
I(t) = 2.5cos(377t- 60°) A
Irms = [tex]\frac{2.5}{\sqrt{2} }[/tex] ∠ -60°
determine complex power apparent power . ...... power factor
Note : complex power = apparent power
=( Irms ) * Vrms
= ( [tex]\frac{2.5}{\sqrt{2} }[/tex] ∠ -60° ) * ( [tex]\frac{100}{\sqrt{2} }[/tex] ∠ -30° )
= 125 ∠ 30°
= ( 108.253 + 62.5 i ) VA ( complex power )
active power = 108.25 watts
reactive power = 62.5 VAR'S
power factor = cos ∅ = cos 30° = 0.866 ( lagging )
current lags voltage by 30°
A steel rod of circular cross section will be used to carry an axial load of 89 kips. The maximum stresses in the rod must be limited to 31 ksi in tension and 14 ksi in shear. Determine the required diameter for the rod.
Answer:
d = 1.9 in
Explanation:
Since, the tension force is greater than the shear force. Hence, the area of cross-section shall be limited by the tension:
Tension = Force/Area
Area = Force/Tension
Area = 89 kips/31 ksi
Area = 2.87 in²
but,
Area = πd²/4
2.87 in² = πd²/4
(2.87 in²)(4)/π = d²
d = √(3.65 in²)
d = 1.9 in
In powershell what commands do these:1. How can we find out the different membertypes (e.g. properties and methods) of the Get-Process cmdlet?2. How can we load the Storage module to the current session?3. How can we gather a list of only the SingularNoun for all the cmdlets currently available in our PS session? Please limit the list to only show the unique noun4. How can we display a list of all available modules that ends with the word "server"?
Answer:
Following are the solution to this question:
Explanation:
In question 1:
It Cmdlet gets the representatives of items, its features including their methods. Now use a variable (InputObject) and pipe the object to Even getting Member for both the purpose of specifying the object. It static variable utilizes their class members, not the case, to gather information regarding static members. Just use the (MemberType) parameter and receive only some forms of participants, such example NoteProperties.
In question 2:
Its Purchase cmdlet allows us to import components through our process. It can import components via remote sessions through the local client beginning with Window PowerShell 3.0.
In question 3:
The Syntax query to have all cmdlets lists it in the cmdlet title alphabetical order, but instead shows them in noun clauses.
Command:
[tex]\text{Type Cmdlet } | \text{Sort-Object -Property Noun} | \text{Format-Table -GroupBy Noun}[/tex]
In question 4:
Syntax:
[tex]\text{Get node} | \text{format list} | \text{Selection process, device forms, route group title all}[/tex]
[tex]| \text{Layout Table} | \text{Selection process}[/tex]
[tex]\$ s[/tex] = New-PSSession -ComputerName Server
Get-Module -PSSession [tex]\$ s[/tex] -ListAvailable
Scientists learn more about the natural world through investigation. This involves identifying a problem, researching related information, designing and conducting an investigation, analyzing the results, evaluating the conclusion, and communicating the findings. Engineers follow similar steps when creating new products or solutions through technological design. The four stages of technological design include identifying a need, designing and implementing a solution, and evaluating the solution.
Answer:
This shows that the technological designs are similar to the scientific investigation processes.
Explanation:
Scientists carry out scientific investigations and discoveries. They learn from their environment by investigating the natural world. The scientist investigates by problem identification, research the related information, designing and conceptualizing, investigating and analyzing the results and deriving out conclusions.
Similarly the engineers follow the same step and provide solutions to the problems of the society through their products and technological designs. The engineers first identify the need of the product, design and implement the design to provide solution and then evaluate the solution. These are the similar steps that an engineer follow in a technological design of a product or a solution.
Es una de las alternativas para obtener capital y como facilidad puede ayudarte a financiarte por más de 40 días, contando con el capital para pagar el saldo.
Answer:
Apalancamiento.
Explanation:
El apalancamiento es el uso de dinero prestado (deuda) para aumentar el rendimiento esperado del capital. El apalancamiento se mide como la relación entre la deuda que devenga intereses y los activos totales. Cuanto mayor sea la deuda que devenga intereses, mayor será el apalancamiento financiero o "aceleración". Esto puede tener un efecto positivo o negativo.
Los costos por intereses de este capital de préstamo suelen ser fijos y se deducen de los ingresos. Un préstamo permite que una organización genere más ingresos sin un aumento necesario en el capital. Como no es necesario recaudar ni mantener capital social adicional, no se requieren pagos de dividendos adicionales (que no se pueden deducir de las ganancias). Sin embargo, un alto apalancamiento puede ser beneficioso durante los tiempos de auge, pero puede conducir a serios problemas de flujo de efectivo durante una recesión, ya que es posible que no haya suficientes retornos para cubrir mayores costos de intereses y obligaciones de reembolso.
A semiconductor, in thermal equilibrium, has a hole concentration of p0 = 2x1016 cm-3. The minority carrier life time = 3x10-7 s. (Assume, ni = 1010 cm-3)
(a) Determine the thermal equilibrium recombination rate of electrons.
(b) Determine the recombination rate of electrons if an excess electron concentration of În = 1013 cm-3 exists.
(c) Calculate the change in the recombination rate when excess electron concentration exists (compared to thermal equilibrium).
Answer:
[tex]1.67\times 10^{9}\ \text{cm}^{-3}\text{s}^{-1}[/tex]
[tex]3.33\times 10^{19}\ \text{cm}^{-3}\text{s}^{-1}[/tex]
[tex]3.33\times 10^{19}\ \text{cm}^{-3}\text{s}^{-1}[/tex]
Explanation:
[tex]p_0[/tex] = Hole concentration = [tex]2\times 10^{16}\ \text{cm}^{-3}[/tex]
[tex]n_i[/tex] = Intrinsic concentration = [tex]10^{10}\ \text{cm}^{-3}[/tex]
[tex]\tau_{n0}[/tex] = Minority carrier life time = [tex]3\times 10^{-6}\ \text{s}[/tex]
[tex]\delta n[/tex] = Excess concentration of electrons = [tex]10^{13}\ \text{cm}^{-3}[/tex]
Majority carrier electron concentration is given by
[tex]n_0=\dfrac{n_i^2}{p_0}\\\Rightarrow n_0=\dfrac{(10^{10})^2}{2\times 10^{16}}\\\Rightarrow n_0=5000\ \text{cm}^{-3}[/tex]
Recombination rate is given by
[tex]R_{n0}=\dfrac{n_0}{\tau_{n0}}\\\Rightarrow R_{n0}=\dfrac{5000}{3\times 10^{-6}}\\\Rightarrow R_{n0}=1.67\times 10^{9}\ \text{cm}^{-3}\text{s}^{-1}[/tex]
The recombination rate is [tex]1.67\times 10^{9}\ \text{cm}^{-3}\text{s}^{-1}[/tex]
Recombination rate is given by
[tex]R_n=\dfrac{\delta_n}{\tau_{n0}}\\\Rightarrow R_n=\dfrac{10^{13}}{3\times 10^{-7}}\\\Rightarrow R_n=3.33\times 10^{19}\ \text{cm}^{-3}\text{s}^{-1}[/tex]
The recombination rate is [tex]3.33\times 10^{19}\ \text{cm}^{-3}\text{s}^{-1}[/tex]
Change in the recombination rate is
[tex]\Delta R_n=3.33\times 10^{19}-1.67\times 10^{9}\\\Rightarrow \Delta R_n=3.33\times 10^{19}\ \text{cm}^{-3}\text{s}^{-1}[/tex]
The change in the recombination rate is [tex]3.33\times 10^{19}\ \text{cm}^{-3}\text{s}^{-1}[/tex]
Water flows with an average velocity of 1.0 m/s and a normal depth of 0.5 m in a wide rectangular channel. Is the flow subcritical or supercritical?
Answer:
Subcritical
Explanation:
To compute the grouse number
We use this formula
F = v/√gy
From this question
V = 1 m
G = 9.81m/sec²
Y = 0.5
When we insert this into the grouse formula
F = 1m/s / √ 9.8m/sec² x 0.5m
= 0.451< 1
Therefore we conclude that the grouse is less than 1 and so the flow is subcritical.
Suppose to build RSA crypto system you picked primes "p" and "q" as 3 and 7 and "e" as 5 what are the public and private keys? What is the encryption of a message whose integer equivalent is 12. Show that the decryption gives back the message 12.
Answer:
1) Public key of the receiver is (e, n) is (5, 21) and Private key of the receiver (d, n) is (5 , 21) ,
2) the encryption of a message whose integer equivalent is 12 is 3
3) Decryption of the message ⇒ P = C^d mod n
⇒ P = 3⁵ mod 21
⇒ P = 243 mod 21
⇒ 12
Explanation:
Given that,
p = 3
q = 7
e = 5
1)
Now, n = pq = 3 × 7 = 21
Ø(n) = (p-1) × (q-1) = 2 × 6 = 12
Public key of the receiver is (e, n) is (5, 21)
and private key of the receiver is (d, n)
we have to find 'd' by using the expression
ed = 1 + kmodØ(n)
d = 1 + kmodØ(n) / e
now to get 'd' , we need to choose the least positive integer 'k', by substituting different values of ‘k’ from 0,
so for k =0 , d = (1+0) / 5 = 0.2 not an integer.
for k =1 , d = (1+12) / 5 = 13/5 = 2.6 not an integer.
for k =2 , d = (1+24) / 5 = 5 , now 5 is an integer
So k = 2 and d = 5
Private key of the receiver (d, n) is (5 , 21)
2)
Now the encryption of a message whose integer equivalent is 12?
Encryption of the message ⇒ C = P^e mod n
⇒ C = 12⁵ mod 21
⇒ 248832 mod 21
⇒ 3
3)
Also the decryption gives back the message 12.
Decryption of the message ⇒ P = C^d mod n
⇒ P = 3⁵ mod 21
⇒ P = 243 mod 21
⇒ 12
A rigid tank contains 2 kg of N2 and 4 kg of Co2 at temperature of 25 C and 1 MPa. Find the partial pressure of each gas respectively?
Answer: Partial pressures are 0.6 MPa for nitrogen gas and 0.4 MPa for carbon dioxide.
Explanation: Dalton's Law of Partial Pressure states when there is a mixture of gases the total pressure is the sum of the pressure of each individual gas:
[tex]P_{total} = P_{1}+P_{2}+...[/tex]
The proportion of each individual gas in the total pressure is expressed in terms of mole fraction:
[tex]X_{i}[/tex] = moles of a gas / total number moles of gas
The rigid tank has total pressure of 1MPa.
Nitrogen gas:molar mass = 14g/mol
mass in the tank = 2000g
number of moles in the tank: [tex]n=\frac{2000}{14}[/tex] = 142.85mols
Carbon Dioxide:molar mass = 44g/mol
mass in the tank = 4000g
number of moles in the tank: [tex]n=\frac{4000}{44}[/tex] = 90.91mols
Total number of moles: 142.85 + 90.91 = 233.76 mols
To calculate partial pressure:
[tex]P_{i}=P_{total}.X_{i}[/tex]
For Nitrogen gas:
[tex]P_{N_{2}}=1.\frac{142.85}{233.76}[/tex]
[tex]P_{N_{2}}[/tex] = 0.6
For Carbon Dioxide:
[tex]P_{total}=P_{N_{2}}+P_{CO_{2}}[/tex]
[tex]P_{CO_{2}} = P_{total}-P_{N_{2}}[/tex]
[tex]P_{CO_{2}}=1-0.6[/tex]
[tex]P_{CO_{2}}=[/tex] 0.4
Partial pressures for N₂ and CO₂ in a rigid tank are 0.6MPa and 0.4MPa, respectively.
Write a python script using while loop which display the number list with an increment of 3 between 1 and 25. Display the output in one row as shown.
Answer:
num_count = 0
while num_count < 25:
print(num_count)
num_count += 3
Explanation:
A while loop statement is defined in the python source code above. An integer variable 'num_count' is defined and continuously incremented by three in the loop until it is greater than 25. the output of the while loop between 1 and 25 is print on the screen.