Answer: power required to maintain level flight=82.20hp
Explanation:
Given
Area = 200 ft^2
Weight = 2000 lb
Cl( Lift coefficient)= 0.39
Cd( Drag coefficient) = 0.06
The density ρ of air at standard atmospheric pressure = 2.38 X 10^-3 slugs/ft^3
For Equilibrium to be maintained during flight conditions, the lift force must be balanced by the weight of the aircraft such that
Lift force = Weight of aircraft
(1/2)ρAU²Cl= W
1/2X 2.38 X 10^-3 X 200 X U² X 0.39 = 2000
U²= 2000 X 2 / 2.38 X 10^-3 X 200 X 0.39
U=[tex]\sqrt{21,547.08}[/tex]
Velocity, U= 146.7892ft/s
Drag force of the velocity can be deduced from the formulae
Cd= Drag force(D) /1/2 ρU²A
Drag force=1/2 ρU²ACd
D=1/2 x (2.38 X 10^-3 slugs/ft^3) x (146.7892ft/s)² x 200 ft^2 x 0.06
D=307.69
Drag force= 308lb
power required to maintain level flight is given as
P = Drag force x Velocity = D x U
=308lb X 146.7892ft/s
=45,211.0736lb.ft/s
Changing to hp we have that
1 Horsepower, hp = 550 ft lbf/s
??=45,211.0736lb.ft/s
45,211.0736lb.ft/s/ 550 ft lbf/s= 82.20hp
A section of highway has a speed-flow relationship of the form q = au 2 + bu. It is known that at capacity (which is 3100 veh/h) the space-mean speed of traffic is 28 mi/h. Determine the speed when the flow is 1500 veh/h and the free-flow speed.
In I-Q modulation technique, many symbols or signals with different amplitude and phase are generated. What is the map of all of the symbols called:____.
a. signal diagram.
b. frequency spectrum.
c. 2-D graph.
d.constellation diagram.
Answer:
In I-Q modulation technique, many symbols or signals with different amplitude and phase are generated. What is the map of all of the symbols called:____.
d. constellation diagram.
Explanation:
A constellation diagram is a representation of all the possible symbols that a system can transmit. It shows these as a collection of points on the map. For a signal modulated by a digital modulation scheme, the constellation diagram is used to display both the ideal (reference) signal and the actual measured signal on the same plot. Modulation simply means the process of converting data into electrical signals so that they are optimized for transmission.
Which of the following is the property that describes the amount of volume that decreases when pressure is applied to a fluid?
O shear stress
O compressibility
O viscosity
O elasticity
Answer:
Compressibility.
Explanation:
The compressibility of a fluid can be defined as a measure of the change in volume (density) with respect to the amount of pressure applied to the fluid. Thus, as the pressure of a compressible fluid increases, both its viscosity and density increases.
Some examples of compressible fluids are vapors, gases, air etc.
Hence, compressibility is the property that describes the amount of volume that decreases when pressure is applied to a fluid.
Additionally, the compressibility of fluids plays a significant role in the field of science such as in aerodynamics, fluid mechanics, thermodynamics etc.
Answer:
compressiblity
Explanation:
How would you handle a situation where another team member was critical of your work?
Suppose the country of Bangladesh wants a low interest loan to invest in the building of infrastructure. Which international organizations would it MOST LIKELY turn to? A. UNDP or UNICEF B. World Bank or UNICEF C. UNDP or World Bank D. UNDP or IMF
Answer:
C. UNDP or World Bank.
Explanation:
Suppose the country of Bangladesh wants a low interest loan to invest in the building of infrastructure. The international organizations which Bangladesh would most likely turn to are UNDP or World Bank.
Cast iron has about how much carbon content?
A)Less than 1%
B)2%
C)3%
D)4% or higher
Answer:
c
Explanation:
Which of the following would be seen as an improvement on the quality of capital or a positive investment? A. Educational test scores are up. B. An assembly line has been closed down. C. Research and development has improved. D. Irrigation systems have been installed.
Answer:
The correct option is;
D. Irrigation systems have been installed
Explanation:
The quality of capital measures the amount of capital available within an economy and the benefit derivable from the capital
Quality of capital is improved by advances in technology which are the outcomes of research and development. With technological advancement, a unit of capital can enable a unit of labor to increase the amount of goods produced
The difference between a farm which uses manual labor to water the plants and a farm which uses an irrigation system is that the farm that uses manual watering techniques has a lower quality of capital per worker than the farm that has an irrigation system, which is a positive investment.
The mechanical properties of a metal may be improved by incorporating fine particles of its oxide. Given that the moduli of elasticity of the metal and oxide are, respectively, 57 GPa and 390 GPa, what is the (a) upper-bound, and (b) lower-bound modulus of elasticity values (in GPa) for a composite that has a composition of 33 vol% of oxide particles.
Answer:
a) the modulus of elasticity upper-bound is 166.89 GPa
b) the modulus of elasticity lower-bound is 79.36 Gpa
Explanation:
For a two-phase composite, modulus of elasticity upper-bound expression is as follows;
Ec(U) = EmVm + EpVp
where Em is the modulus of elasticity of matrix, Ep is the modulus of elasticity of patriciate phase, Ec is the modulus of elasticity of composite, Vm is the volume fraction of matrix and Vp is the volume fraction of composite.
Also for a two-phase composite, modulus of elasticity lower-bound expression is as follows;
Ec(L) = (EmEp) / ( VmEp + VpEm)
a)
Now lets consider the expression of rule of mixtures for upper-bound and calculate the modulus of elasticity upper-bound.
Ec(U) = EmVm + EpVp --------- equ 1
Vm + Vp = 1
given that Vp = 33 vol% = 0.33, we substitute
Vm + 0.33 = 1
Vm = 0.67
so from our equation 1
we substitute our given data; Em = 57 Gpa, Ep = 390 Gpa, Vm = 0.67, Vp = 0.33
Ec(U) = EmVm + EpVp
Ec(U) = ( 57 × 0.67) + ( 390 × 0.33)
Ec(U) = 38.19 + 128.7
Ec(U) = 166.89 GPa
Therefore the modulus of elasticity upper-bound is 166.89 GPa
b)
Now lets consider the expression of rule of mixtures for lower-bound and calculate the modulus of elasticity upper-bound.
Ec(L) = (EmEp) / ( VmEp + VpEm)
we substitute our values
Ec(L) = (57 × 390) / ( (0.67 × 390) + (0.33 × 57)
Ec(L) = 22230 / ( 261.3 + 18.81)
Ec(L) = 22230 / 280.11
Ec(L) = 79.36 Gpa
Therefore the modulus of elasticity lower-bound is 79.36 Gpa
Two blocks, one 0.8 kg and the other 2.0 kg are connected by a massless string over a frictionless pulley. The coefficient of kinetic friction is 0.14, and the downward ramp angle is 60 degrees.
a. Determine the acceleration of the blocks.
b. Calculate the tension of the string.
Answer:
a) 4.58m/s²
b) 10.454N
Explanation:
According to Newton second law, the following simultaneous equation will be applicable
T - Fm = m1a.... 1
W - T = m2a ....2
m1 and m2 are the masses
T is the tension of the string
W is the weight of mass m2
Fm is the force acting along the incline
Fm = m1gsin theta
W = m2g
a) Add both equation to eliminate tension T
W-Fm = m1a+m2a
m2g - m1gsin theta = (m1+m2)a
Substitute the given values
2(9.8)-0.8(9.8)sin60 = (2+0.8)a
19.6-6.79 = 2.8a
12.81 = 2.8a
a = 12.81/2.8
a = 4.58m/s²
Hence the acceleration of the blocks is 4.58m/s2
b) Get the Tension T
Substitute the acceleration gotten in (a) into equation 1 as shown:
From 1:
T - Fm = m1a
T = m1a+Fm
T = 0.8(4.58)+m1gsintheta
T = 0.8(4.58)+0.8(9.8)sin60
T = 3.664+6.79
T = 10.454N
Hence the tension in the string is 10.454N
ldentiy three industries that often need the skills of mechanical engineers. Briefly explain the skills that mechanical engineers bring to these
industries.
Answer:
3 industries that often need the skills of mechanical engineers are:
Automotive industry Construction industry Aerospace industryThe key skills mechanical engineers bring to these industries are effective technical skills, the ability to work under pressure, problem-solving skills, creativity and teamwork.
Explanation:
Automotive industry: The skills mechanical engineers bring to automotive industry include designing new cars for development, conducting laboratory testing for performance safety, and troubleshooting design or manufacturing issues with recalled vehicles. Automotive engineers have:
good mathematical skills, for instance in calculating the stresses power trains and other parts have to withstand; understanding and application of principles of physics and chemistry to properly design engines, electrical systems and other car components; good computer skills, because 21st century engineers rely on computer-assisted design software; knowledge of ergonomics, which is applied in the process of designing a car so that the driver and passengers have a comfortable and functional environment, is another skill mechanical; engineers need.Construction industry: Mechanical engineers are responsible for designing, building, establishing, and maintaining all kinds of mechanical machinery, tools, and components in the construction industry.
Aerospace industry: Mechanical engineers in aerospace industry produce specifications for design, development, manufacture and installing of new or modified mechanical components or systems. They design more fuel-efficient aircraft that cut emissions and build the fleets of satellites that power modern GPS technology.
A W18 X 119 is used as a compression member with one end fixed and the other end pinned. The length is 12 feet. What is the design compressive strength of A992 steel is used
Answer:
156.0 ksi
Explanation:
The formula of compressive strength is CS = F / A
where F is the force or load while A is the cross-sectional area
Given the inertia Ag = 35.1 in^4 , which is less than 40, the steel has a short column.
E = 29000 ksi
L = 12ft
r = 2.69 in
therefore;
CS = π^2 E / (kL^2/r)^2
= π^2 29000 / (0.8 x 12^2 / 2.69)^2
= 286292.756 / 1834.4089 = 156 ksi
Estimate the heating energy requirements for a residential building using the degree-day method (a) in Denver, Colorado, and (b) in Little Rock, Arkansas. The overall heat loss coefficient is 400 Btu/h.oF and the furnace efficiency is 0.78.
Answer:
a) 600°F days
b) 103°F days
Explanation:
Given data :
overall heat loss coefficient = 400 Btu/h.oF
Furnace efficiency = 0.78
applying the degree- day method the heating energy requirement per day can be obtained by subtracting the average temperature for a particular day from the acceptable mid/balance point temperature
lets assume the mid/balance point temperature = 65°F
a) heating energy requirement in Denver Colorado
we will have 600°F days ; considering the the average temperature - balance point temperature
= 665 - 65 = 600°F
b) heating energy requirement in Little Rock Arkansas
we will have 103° days