Answer:
The answer is below
Explanation:
Given that:
x = 5 cm = 0.05 m, width (w) = 5 cm = 0.05 m, thickness (t) = 1 mm = 0.001 m, k = thermal conductivity = 200 W/mK, h = heat transfer coefficient = 22 W/m².K, Tb = base temperature = 40°C, T∞ = 20°C
[tex]m=\sqrt{ \frac{hp}{kA} }=\sqrt {\frac{22*(2*0.05+2*0.001)}{200*(0.05*0.001)}} =15\ m^{-1}\\\\\frac{T-T_{\infty}}{T_b-T_{\infty}} =e^{-mx}\\\\\frac{T-20}{40-20} =e^{-15*0.05}\\\\T-20=9.45\\\\T=29.45^oC\\\\The\ rate\ of\ heat\ loss\ is:\\\\\dot{Q}=\sqrt{hpkA}(T_b-T_{\infty})\\ \\\dot{Q}=\sqrt{22*(2*0.05+2*0.001)*200*0.05*0.001}*(40-20)\\\\\dot{Q}=3\ W[/tex]
Make a proposal to add a small pizza shop to a historical part of town. How could it be designed to “fit” into the area?
A commercial jet is flying at a standard altitude of 35,000 ft with a velocity of 550 mph: (a) what is the Mach number? (b) should the flow be treated as incompressible, why or why not?
Answer:
Mach number = 0.68168
The flow should be treated as compressible.
Explanation:
Given that:
The altitude of a commercial jet = 35000
The properties of air at that given altitude are as follows:
Pressure = 24.577 kPa
Temperature T = 50.78176° C
Temperature T = ( 50.78176 + 273 )K = 328.78176 K
[tex]\varphi = 0.38428 \ kg/m^3[/tex]
The velocity is also given as: 550 mph = 245.872 m/s
Therefore, the sonic velocity is firstly determined by using the formula:
[tex]a = \sqrt{ \vartheta \times R \times T\[/tex]
[tex]a = \sqrt{1.4 \times 287 \times 323.78176[/tex]
[tex]a = \sqrt{130095.5112[/tex]
a = 360.68755 m/s
Then, we can calculate the Mach number by using the expression:
[tex]{Mach \ number = \dfrac{V}{a}}[/tex]
[tex]Mach \ number = \dfrac{245.872}{360.68755}[/tex]
Mach number = 0.68168
b) Ideally, all flows are compressible because the Mach number is greater than 0.3, suppose the Mach number is lesser than 0.3, then it is incompressible.
This can change the fit of your respirator A) A mustache B) A beard C) Weight gain D) All of the above
Answer:
A) A mustache
B) A beard
Explanation:
A respirator is a device which is worn over the face to aid breathing through the use of oxygen. Because the fit is won on the face a mustache, or beard would change the fit of the respirator of the face as this would make the respirator tighter in some cases while in others not fit at all.
Answer: D) All of the above!
Explanation:
What is the meaning of *binuhat lakas nang loob na ibinaon
Answer:
carried courage buried
Explanation:
its Filipino
Use the following clues to help fill in the chart on the next page. Put an X in the spaces that are INCORRECT and Highlight the
CORRECT
1 The wizard with the lavender wand is in Ravenel or Sparrowan, and earned 50 or 60 points
2. Gorgonscale earned 10 points less than Sparrowman
3 Lynn scored 20 points less than the wizard with the incense wand.
4. Timmy scored 70 or 80 points. He is in Gorgonscale or Hydraden
5. Among Bennie and the wizard from Sparrowan, one earned 70 points and the other has the lavender wand.
6. The mandragore wand belongs to Edward or to the House of Hydraden
7 Ravenel didn't earn 60 points and Edward is not among it's wizards
8. Bennie scored 10 points more than Edward
9. The wizard with the mandragore wand didn't earn 70 points.
Legal metrology would protect consumers from businesses that do not take measurements according to defined measuring regulations.
From what my research concluded, true
Za answa iz:
True
Twust meh
A 30-mm-diameter shaft, made of AISI 1018 HR steel, transmits 10 kW of power while rotating at 200 rev/min. Assume any bending moments present in the shaft to be negligibly small compared to the torque. Determine the static factor of safety based on:a) The maximum-shear-stress failure theory.b) The distortion-energy failure theory.
Answer:
a) According to the maximum-shear-stress failure theory, the static factor of safety of the shaft is 2.440.
b) According to the distortion-energy failure theory, the static factor of safety of the shaft is 2.816.
Explanation:
First, we need to determine the torque experimented by the shaft ([tex]T[/tex]), measured in kilonewton-meters, whose formula is described:
[tex]T = \frac{\dot W}{\omega}[/tex] (Eq. 1)
Where:
[tex]\dot W[/tex] - Power, measured in kilowatts.
[tex]\omega[/tex] - Angular velocity, measured in radians per second.
If we know that [tex]\dot W = 10\,kW[/tex] and [tex]\omega = 20.944\,\frac{rad}{s}[/tex], then the torque experimented by the shaft:
[tex]T = \frac{10\,kW}{20.944\,\frac{rad}{s} }[/tex]
[tex]T =0.478\,kN\cdot m[/tex]
Let consider that shaft has a circular form, such that shear stress is determined by the following formula:
[tex]\tau = \frac{16\cdot T}{\pi\cdot D^{3}}[/tex] (Eq. 2)
Where:
[tex]D[/tex] - Diameter of the shaft, measured in meters.
[tex]\tau[/tex] - Torsional shear stress, measured in kilopascals.
If we know that [tex]D = 0.03\,m[/tex] and [tex]T =0.478\,kN\cdot m[/tex], the torsional shear stress is:
[tex]\tau = \frac{16\cdot (0.478\,kN\cdot m)}{\pi\cdot (0.03\,m)^{3}}[/tex]
[tex]\tau \approx 90164.223\,kPa[/tex]
a) According to the maximum-shear-stress failure theory, we get that maximum shear stress limit is:
[tex]S_{ys} = 0.5\cdot S_{ut}[/tex] (Eq. 3)
Where:
[tex]S_{ys}[/tex] - Ultimate shear stress, measured in kilopascals.
[tex]S_{ut}[/tex] - Ultimate tensile stress, measured in kilopascals.
If we know that [tex]S_{ut} = 440\times 10^{3}\,kPa[/tex], the ultimate shear stress of the material is:
[tex]S_{ys} = 0.5\cdot (440\times 10^{3}\,kPa)[/tex]
[tex]S_{ys} = 220\times 10^{3}\,kPa[/tex]
Lastly, the static factor of safety of the shaft ([tex]n[/tex]), dimensionless, is:
[tex]n = \frac{S_{ys}}{\tau}[/tex] (Eq. 4)
If we know that [tex]S_{ys} = 220\times 10^{3}\,kPa[/tex] and [tex]\tau \approx 90164.223\,kPa[/tex], the static factor of safety of the shaft is:
[tex]n = \frac{220\times 10^{3}\,kPa}{90164.223\,kPa}[/tex]
[tex]n = 2.440[/tex]
According to the maximum-shear-stress failure theory, the static factor of safety of the shaft is 2.440.
b) According to the distortion-energy failure theory, we get that maximum shear stress limit is:
[tex]S_{ys} = 0.577\cdot S_{ut}[/tex] (Eq. 5)
If we know that [tex]S_{ut} = 440\times 10^{3}\,kPa[/tex], the ultimate shear stress of the material is:
[tex]S_{ys} = 0.577\cdot (440\times 10^{3}\,kPa)[/tex]
[tex]S_{ys} = 253.88\times 10^{3}\,kPa[/tex]
Lastly, the static factor of safety of the shaft is:
[tex]n = \frac{253.88\times 10^{3}\,kPa}{90164.223\,kPa}[/tex]
[tex]n = 2.816[/tex]
According to the distortion-energy failure theory, the static factor of safety of the shaft is 2.816.
A car generator turns at 400 rpm (revolutions per minute) when the engine is idling. It has a rectangular coil with 300 turns of dimensions 5.00 cm by 6.11 cm that rotates in an adjustable magnetic field. What is the field strength needed to produce a 24.0 V peak emf?
Answer:
The field strength needed is 0.625 T
Explanation:
Given;
angular frequency, ω = 400 rpm = (2π /60) x (400) = 41.893 rad/s
area of the rectangular coil, A = L x B = 0.0611 x 0.05 = 0.003055 m²
number of tuns of the coil, N = 300 turns
peak emf = 24 V
The peak emf is given by;
emf₀ = NABω
B = (emf₀ ) / (NA ω)
B = (24) / (300 x 0.003055 x 41.893)
B = 0.625 T
Therefore, the field strength needed is 0.625 T
(TCO 7) Find the resolution of the Fourier transform if a signal is sampled at 16,384 samples/second and we collect a total of 8,192 data points and then apply the FFT algorithm to them.
Answer:
Resolution of Fourier transform = 2Hz
Explanation:
Given:
Sample signals = 16,384 samples/second
Number of data points = 8,192 oints
Find:
Resolution of Fourier transform
Computation:
Resolution of Fourier transform = fs / N
Resolution of Fourier transform = 16,384 / 8,192
Resolution of Fourier transform = 2Hz
inspections may be_____ or limited to a specific area such as electrical or plumbing
A. Metering
B. General
1. A gas pressure difference is applied to the legs of a U-tube manometer filled with a liquid with S = 1.5. The manometer reading is 286 mm. Find the pressure difference in kPa. (10 points)
2. Convert the pressure 2.5 psi into units of inches of mercury and feet of water (10 points)
Answer:
1) The pressure difference is 4.207 kilopascals.
2) 2.5 pounds per square inch equals 5.093 inches of mercury and 5.768 feet of water.
Explanation:
1) We can calculate the gas pressure difference from the U-tube manometer by using the following hydrostatic formula:
[tex]\Delta P = \frac{S\cdot \rho_{w}\cdot g \cdot \Delta h}{1000}[/tex] (Eq. 1)
Where:
[tex]S[/tex] - Relative density, dimensionless.
[tex]\rho_{w}[/tex] - Density of water, measured in kilograms per cubic meter.
[tex]g[/tex] - Gravitational acceleration, measured in meters per square second.
[tex]\Delta h[/tex] - Height difference in the U-tube manometer, measured in meters.
[tex]\Delta P[/tex] - Gas pressure difference, measured in kilopascals.
If we know that [tex]S = 1.5[/tex], [tex]\rho_{w} = 1000\,\frac{kg}{m^{3}}[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex] and [tex]\Delta h = 0.286\,m[/tex], then the pressure difference is:
[tex]\Delta P = \frac{1.5\cdot \left(1000\,\frac{kg}{m^{3}} \right)\cdot \left(9.807\,\frac{m}{s^{2}} \right)\cdot (0.286\,m)}{1000}[/tex]
[tex]\Delta P = 4.207\,kPa[/tex]
The pressure difference is 4.207 kilopascals.
2) From Physics we remember that a pound per square unit equals 2.036 inches of mercury and 2.307 feet of water and we must multiply the given pressure by corresponding conversion unit: ([tex]p = 2.5\,psi[/tex])
[tex]p = 2.5\,psi\times 2.037\,\frac{in\,Hg}{psi}[/tex]
[tex]p = 5.093\,in\,Hg[/tex]
[tex]p = 2.5\,psi\times 2.307\,\frac{ft\,H_{2}O}{psi}[/tex]
[tex]p = 5.768\,ft\,H_{2}O[/tex]
2.5 pounds per square inch equals 5.093 inches of mercury and 5.768 feet of water.
Two vehicles collided head on while traveling on a curve tangent with a 3% grade. Vehicle V1 skidded 195 feet downhill before colliding with vehicle V2. Vehicle V2 skidded 130 feet. The police report estimates that the speed of both vehicles at impact was 25 mph, based on vehicle deformation. Assume a coefficient of friction of 0.48. What is V1 speed at the beginning of the skid?
Answer:
Speed V1 at the beginning of the skid = 57.075 mph
Explanation:
Calculate the V1 speed at the beginning of the skid
V1 ( speed before brake was applied ) = ?
distance travelled by Vehicle 1 = 195 ft
curve tangent for vehicle 1 = - 3% = - 0.03
coefficient of friction = 0.48
speed at Impact = 25 mph
To determine the V1 speed at the beginning of the skid we have to apply AASTHO
d1 = [tex]( \frac{VA^{2} - VA^{12} }{30(F+N)} )[/tex]
195 = [tex](\frac{VA^2- 25^2}{30(0.48-0.03)} )[/tex]
Hence : VA = 57.075 mph
It is desired to enrich the partial pressure of hydrogen in a hydrogen–nitrogen gas mixture for which the partial pressures of both gases are 0.1013 MPa (1 atm). It has been proposed to accomplish this by passing both gases through a thin sheet of some metal at an elevated temperature; in as much as hydrogen diffuses through the plate at a higher rate than does nitrogen, the partial pressure of hydrogen will be higher on the exit side of the sheet. The design calls for partial pressures of 0.051 MPa (0.5 atm) and 0.01013 MPa (0.1 atm), respectively, for hydrogen and nitrogen. The concentrations of hydrogen and nitrogen (CHC
H and CNC N , in mol/m3mol/m
3 ) in this metal are functions of gas partial pressures (pH2 and pN2p
H 2 and p N , in MPa) and absolute temperature and are given by the following expressions:
CH=2.5×103√pH2exp(−27,800J/mol/RT)
CN=2.75×103√pN2exp(−37,600J/mol/RT )
Furthermore, the diffusion coefficients for the diffusion of these gases in this metal are functions of the absolute temperature, as follows:
DH(m2/s)=1.4×10−7exp(−13,400J/mol/RT)
DN(m2/s)=3.0×10−7exp(−76,150J/mol/RT)
Is it possible to purify hydrogen gas in this manner? If so, specify a temperature at which the process may be carried out, and also the thickness of metal sheet that would be required. If this procedure is not possible, then state the reason(s) why.
Answer:
T = 3460 K
Explanation:
See attachment for calculation.
Since the temperature we have is above the melting point of the metal, then we can conclude that it is too high for the diffusion process to be possible.
To determine if a product or substance being used is hazardous, consult:__________.
a. A dictionary
b. An MSDS
c. SAE standards
d. EPA guidelines
Answer:
Option B: An MSDS
Explanation:
A dictionary is used to check up the meaning of general words and not for checking if a substance being used is hazardous. Option A is wrong.
MSDS means "Material Safety Data Sheet" and it contains documents with information that relates to occupational health & safety for checking various substances and products. Thus, option B is correct.
SAE stands for Society of Automotive Engineering and their standards pertain to mainly Automobiles. Thus option C is wrong.
EPA guidelines are mainly for checking facility and environmental health and safety compliance. Thus, option D is wrong.
Estimate the rotor inertia assuming that the rotor is a cylinder of radius 8.98 mm, and length 25 mm, with a material of 100% copper. Explain why the rotor inertia may differ from these assumptions?
Answer:
The moment of inertia of the rotor is approximately [tex]1.105\times 10^{-6}[/tex] kilogram-square meters.
The rotor inertia may differ from these assumption due to differences in the shape of cross section.
Explanation:
We assume that rotor can be represented as a solid cylinder of radius [tex]r[/tex], length [tex]l[/tex], made of cooper ([tex]\rho = 8960\,\frac{kg}{m^{3}}[/tex]) and whose axis of rotation passes through its center of mass and is parallel to its cross section. By definition of Moment of Inertia and Theorem of Parallel Axes, the moment of inertia of the rotot is:
[tex]I = \frac{1}{4}\cdot \rho \cdot \left(\frac{\pi}{4} \right) \cdot R^{3}\cdot (3\cdot R^{2}+L^{2})[/tex]
[tex]I = \frac{\pi}{16}\cdot \rho \cdot R^{3}\cdot (3\cdot R^{2}+L^{2})[/tex] (Eq. 1)
Where:
[tex]\rho[/tex] - Density of copper, measured in kilograms per cubic meter.
[tex]R[/tex] - Radius of the rotor, measured in meters.
[tex]L[/tex] - Length of the rotor, measured in meters.
[tex]I[/tex] - Moment of inertia, measured in kilogram-square meters.
If we know that [tex]\rho = 8960\,\frac{kg}{m^{3}}[/tex], [tex]L = 25\times 10^{-3}\,m[/tex] and [tex]R = 8.98\times 10^{-3}\,m[/tex], the estimated moment of inertia of the rotor is:
[tex]I = \frac{\pi}{16}\cdot \left(8960\,\frac{kg}{m^{3}} \right)\cdot (8.98\times 10^{-3}\,m)^{3}\cdot [3\cdot (8.98\times 10^{-3}\,m)^{2}+(25\times 10^{-3}\,m)^{2}][/tex]
[tex]I \approx 1.105\times 10^{-6}\,kg\cdot m^{2}[/tex]
The moment of inertia of the rotor is approximately [tex]1.105\times 10^{-6}[/tex] kilogram-square meters.
From D'Alembert's Formula we know that net force of rigid bodies experimenting rotation equals the product of moment of inertia and angular acceleration. In this case, the purpose is minimizing moment of inertia and it is done by modifying the shape of the cross section so that rotor could be aerodynamically more efficient.
How natural gas works and operates?
PLEASE HELP!!!
Which metal is stronger? Tungsten or Titanium?
Answer:
i believe tungsten is stronger than titanium !
What is the stress term called which is a measure of the stiffness or resistance to deflection?
Modulus of Elasticity (E)
Extreme Fiber Bending (F )
Horizontal Shear Parallel to the Grain (F //)
Compression Perpendicular to the Grain (F z )
Answer:Modulus of Elasticity (E)-------- A
Explanation:
The modulus of elasticity, Young's modulus E is a measure of a material's stiffness or resistance to being elastically deformed when stressed or due to tension According to Hook's law the modulus of elasticity is defined as the ratio of the stress to the strain and defined as the slope of its stress-strain region in the stress and strain graph.
--The stiffer a material, the higher the elastic modulus and vice versa for a less stiff material.
it can be calculated with this formulae
Young’s modulus equation is E = tensile stress/tensile strain
= (FL) / (A X change in L)
where F = applied force,
L = initial length,
A = square area,
E = Young’s modulus in Pascals (Pa).
Before you calculate the moment capacity for a steel beam, you have to determine the classification of beam.
a. True
b. False
Answer:
True
Explanation:
True - because different classification of steel beam have different yield strength.
The moment capacity for a steel beam is given by;
M = Mn / Ωₙ
where;
M - the maximum moment acting on the beam
Ωₙ - is the Safety Factor for Elements in Bending = 1.67
Mn - nominal moment of the steel, given as
[tex]M_n = Z_x *f_y[/tex]
where;
Zₓ - the Plastic Section Modulus in the x or strong axis.
[tex]f_y -[/tex] is the Yield Strength of the Steel (A36W, A46 W or A50W)
A36W = 36 ksi
A46 W = 46 ksi
A50W = 50 ksi
Thus, before you calculate the moment capacity for a steel beam, you have to determine the classification of beam, for the yield strength of the steel beam.
due at 11:59pm please help
Which of the items shown in the photo were developed using engineering design processes to develop a solution to a problem?
A. computer
B. coffee cup
C. table
D. pen
An engineer proposes that a newly developed chemical could be sprayed from aircraft to slow the rate of burning in a forest fire. What is the next step the engineer is likely to take to develop a solution to fighting forest fires?
A. test a number of similar chemicals
B. spray and compare the effectiveness of each tested chemical to water.
C. add the chemical to all aircraft spray tanks.
D. design a spray system for the chemical.
Facts about cellphones
Answer:
Your mobile phone has more computing power than the computers used for the Apollo 11 moon landing.
Mobile phones have to “work harder” to get a signal if you are in a moving vehicle.
The first mobile phone was made in 1973.
The first mobile phones that went on sale in 1983 cost nearly $4,000 each.
In 2012 Apple sold 340,000 phones per day.
4 out of 10 Brits admit to snooping on their partners phone.
Out of the 53% of snoopers that found incriminating evidence on their partner’s phone, 5% went on to terminate their relationship.
Waterproof mobile phones came to market because Japanese youngsters like to use them in the shower.
Apparently mobile phones have 18 times more bacteria on them than toilet handles!
Phubbing describes the act of snubbing someone by using your mobile phone in their company.
In 2015 more people died from taking selfies than shark attacks.
Teenagers that use a phone more than 2 hours a day increase their risk of depression and anxiety.
Nomobophobia is severe anxiety caused by the thought or act of losing your phone or running out of battery.
Explanation:
what is the discount on airpod pro thank you screen
Answer:
190$-200$
Explanation:
2) Why should you use a standard resistor so that the balance point is near the center of the bridge?
Answer:
Explanation:
I think I will say it is because most, if not all resistors have been made to standard already.
The value for the resistor that is chosen for two fixed arms from the Wheatstone Bridge have to be quite bear each other, as much as possible. The arm that moves and the other that doesn't move, their resistance values are made to be quite close as well. This makes the resistance of the arm that moves to be set somewhere in the middle, and as a result, the measurements don't exceed beyond the resistance range of the arm that moves.
I hope you understand?
Should transistors used in switching circuits be biased in the active region? Why or why not?
Answer:
no
Explanation:
No. More power is dissipated when the transistor is in its active region. In general, transistors in switching circuits are biased either "on" or "off". Time spent in the active region is minimized.
_____
On the other hand, speed can be enhanced if the transistors are active. So, it's a speed/power trade-off. Usually power is of more interest, particularly when there are millions of switching circuits. However, in certain applications, speed may be the priority, so the transistor will be biased in its active region.
________ is the most theoretical computing discipline, focusing mostly on finding new and better ways for computers to work
Answer:
Computer science
Explanation:
Computer science is the most theoretical computing discipline, focusing mostly on finding new and better ways for computers to work.
What is computer programming?The process of carrying out a specific computation through the design and construction of an executable computer program is known as computer programming.
Tasks like analysis, creating algorithms, and assessing the precision and resource use of those algorithms are all part of programming.
As we know,
The study of computing, robotics, and information is known as computer science. Algorithmic, computing theory, information theory, and automation are examples of academic areas in computer science.
Thus, computer science is the most theoretical computing discipline, focusing mostly on finding new and better ways for computers to work.
Learn more about computer programming here:
brainly.com/question/14618533
#SPJ2
Recently, due to rapid urbanization and mechanization residents of a city are suffering from harmful effects of the ultra violet rays. Depletion of which layer is likely to have led to this situation
The critical resolved shear stress for a metal is 36 MPa. Determine the maximum possible yield strength (in MPa) for a single crystal of this metal that is pulled in tension.
Answer:
72 MPa
Explanation:
Critical resolved shear stress = 36 MPa
calculate the maximum possible yield strength for a single crystal of the metal
first we have to express the critical resolved shear stress as
бy = 2т[tex]_{critical}[/tex]
given that the minimum stress needed to introduce yielding curve will occur at Ψ = λ = 45
where : бy = yielding stress
t[tex]_{critical}[/tex] = 36MPa
therefore the maximum possible yield strength
= (2) * (36)
= 72 MPa
what is most delicious fod in the philippines?
Answer:
Well there are a lot of delicious food in the philppines but my most favorite is the Lechon, Adobo, Sisig, Chicken Curry, Crispy pata and Sinigang
A hypothetical metal has the simple cubic (SC) crystal structure. If its atomic weight is 70.4 g/mol and the atomic radius is 0.126 nm. Compute its density (in g/cm3)
Answer:
[tex]7304g/cm^3[/tex]
Explanation:
Density is the mass per unit volume, it is usually measured in kg/m³.
The density of a crystal structure is given by:
[tex]\rho=\frac{mass\ of\ atoms\ in\ unit\ cell}{volume\ unit\ cell} =\frac{nA}{V_cN_A} \\\\\rho=density, n= number\ of\ atoms/unit=1\ atom/unit\ cell,A=atomic\ weight=70.4\ g/mol,N_A=avogadro\ constant=6.023*10^{23}atoms/mol,V=volume=2R^3=[2(0.126*10^{-8})]^3cm\\\\\rho=\frac{1*70.4}{[2(0.126*10^{-8})]^3*6.023*10^{23}} =7304g/cm^3[/tex]
Answer:
7.307g/cm^3
Explanation:
The other guy is mostly right but his conversion factor was off. It should be 1.26x10^-8 on the bottom
What shortcoming does a parity bit have when used as an error detection scheme for a sequence of ones and zeros
Answer:
It only detects errors if an odd number of bit flips have occurred.
Explanation:
Parity is a measure of how even or odd a string of digits (for example, a string of binary units is). It is obtained by calculating the value of all the bits. Parity is used in error detection. A parity error is detected when the parity and the odd number of bits are incorrectly propagated.
A problem commonly associated with the parity bits is that they can only detect an odd number of bit errors. This means that if a digit is corrupted in the even binary digits there would be an incorrect detection of errors.
