Air at 27°C and a velocity of 5 m/s passes over the small region As (20 mm × 20 mm) on a large surface, which is maintained at Ts = 127°C. For these conditions, 0.5 W is removed from the surface As. To increase the heat removal rate, a stainless steel (AISI 304) pin fin of diameter 5 mm is affixed to As, which is assumed to remain at Ts = 127°C. (a) Determine the maximum possible heat removal rate through the fin. (Hint: look back to Chapter 3 to see which fin case produces the maximum heat transfer.) (b) What fin length would provide a close approximation to the heat rate found in part (a)? (Hint: refer to Example 3.9.) (c) Determine the fin effectiveness, εf. (d) What is the percentage increase in the heat rate from As due to installation of the fin? In other words, what is the percentage increase in q obtained by adding the fin as compared to not having the fin?

Answers

Answer 1

Answer:

a) The maximum possible heat removal rate = 2.20w

b) Fin length = 37.4 mm

c) Fin effectiveness = 89.6

d) Percentage increase = 435%

Explanation:

See the attached file for the explanation.

Air At 27C And A Velocity Of 5 M/s Passes Over The Small Region As (20 Mm 20 Mm) On A Large Surface,
Air At 27C And A Velocity Of 5 M/s Passes Over The Small Region As (20 Mm 20 Mm) On A Large Surface,
Air At 27C And A Velocity Of 5 M/s Passes Over The Small Region As (20 Mm 20 Mm) On A Large Surface,
Air At 27C And A Velocity Of 5 M/s Passes Over The Small Region As (20 Mm 20 Mm) On A Large Surface,

Related Questions

16.44 Lab 13D: Student Scores with Files and Functions Overview Create a program that reads from multiple input files and calls a user-defined function. Objectives Gain familiarity with CSV files Perform calculations with data from CSV files Create a user-defined function Read from multiple files in the same program

Answers

Answer:

See Explaination

Explanation:

# copy the function you have this is just for my convenniece

def finalGrade(scoresList):

weights = [0.05, 0.05, 0.40, 0.50]

grade = 0

for i in range(len(scoresList)):

grade += float(scoresList[i]) * weights[i]

return grade

import csv

def main():

with open('something.csv', newline='') as csvfile:

spamreader = csv.reader(csvfile, delimiter=',', quotechar='|')

file = open('something.txt')

for row in spamreader:

student = file.readline().strip()

scores = row

print(student, finalGrade(scores))

if __name__ == "__main__":

main()

5.3-16 A professor recently received an unexpected $10 (a futile bribe attached to a test). Being the savvy investor that she is, the professor decides to invest the $10 into a savings account that earns 0.5% interest compounded monthly (6.17% APY). Furthermore, she decides to supplement this initial investment with an additional $5 deposit made every month, beginning the month immediately following her initial investment.
(a) Model the professor's savings account as a constant coefficient linear difference equation. Designate yln] as the account balance at month n, where n corresponds to the first month that interest is awarded (and that her $5 deposits begin).
(b) Determine a closed-form solution for y[n] That is, you should express yIn] as a function only of n.
(c) If we consider the professor's bank account as a system, what is the system impulse response h[n]? What is the system transfer function Hz]?
(d) Explain this fact: if the input to the professor's bank account is the everlasting exponential xn] 1 is not y[n] I"H[I]-HII]. 1, then the output

Answers

Answer:

a) y (n + 1) = 1.005 y(n) + 5U n

y (n + 1) - 1.005 y(n) = 5U (n)

b) Z^-1(Z(y0)=y(n) = [1010(1.005)^n - 1000(1)^n] U(n)

c) h(n) = (1.005)^n U(n - 1) + 10(1.005)^n U(n)

Explanation:

Her bank account can be modeled as:

y (n + 1) = y (n) + 0.5% y(n) + $5

y (n + 1) = 1.005 y(n) + 5U n

Given that y (0) = $10

y (n + 1) - 1.005 y(n) = 5U (n)

Apply Z transform on both sides

= ZY ((Z) - Z(y0) - 1.005) Z = 5 U (Z)

U(Z) = Z {U(n)} = Z/ Z - 1

Y(Z) [Z- 1.005] = Z y(0) + 5Z/ Z - 1

= 10Z/ Z - 1.005 + 5Z/(Z - 1) (Z - 1.005)

Y(Z) = 10Z/ Z - 1.005 + 1000Z/ Z - 1.005 + 1000Z/ Z - 1

= 1010Z/Z- 1.005 - 1000Z/Z-1

Apply inverse Z transform

Z^-1(Z(y0)) = y(n) = [1010(1.005)^n - 1000(1)^n] U(n)

Impulse response in output when input f(n) = S(n)

That is,

y(n + 1)= 1. 005y (n) + 8n

y(n + 1) - 1.005y (n) = 8n

Apply Z transform

ZY (Z) - Z(y0) - 1.005y(Z) = 1

HZ (Z - 1.005) = 1 + 10Z [Therefore y(Z) = H(Z)]

H(Z) = 1/ Z - 1.005 + 10Z/Z - 1. 005

Apply inverse laplace transform

= h(n) = (1.005)^n U(n - 1) + 10(1.005)^n U(n)

8 A static load test has been conducted on a 60 ft long, 16 in square reinforced concrete pile which has been driven from a barge through 20 ft of water, then 31 ft into the underlying soil. Telltale rods A and B have been embedded at points 30 ft and 59 ft from the top of the pile, respectively. The data recorded at failure was as follows: Load at head = 139,220 lb, settlement at head = 1.211 in, settlement of telltale rod A = 1.166 in,settlement of telltale rod B = 1.141 in. Use the data from telltale rod A to compute the modulus of elasticity of the pile, then use this value and the remaining data to compute q′n and the average fn value.

Answers

Answer:

Modulus of Elasticity = 4.350×10⁶ lb/in²

q'n = 60.33 lb/in²

Side friction = 6.372 lb/in²

Explanation:

See workings in picture below.

Air enters a compressor operating at steady state at 1.05 bar, 300 K, with a volumetric flow rate of 39 m3/min and exits at 12 bar, 400 K. Heat transfer occurs at a rate of 6.5 kW from the compressor to its surroundings. Assuming the ideal gas model for air and neglecting kinetic and potential energy effects, determine the power input, in kW.

Answers

Answer:

The power input, in kW is -86.396 kW

Explanation:

Given;

initial pressure, P₁ = 1.05 bar

final pressure, P₂ = 12 bar

initial temperature, T₁ = 300 K

final temperature, T₂ = 400 K

Heat transfer, Q = 6.5 kW

volumetric flow rate, V = 39 m³/min = 0.65 m³/s

mass of air, m = 28.97 kg/mol

gas constant, R = 8.314 kJ/mol.k

R' = R/m

R' = 8.314 /28.97 = 0.28699 kJ/kg.K

Step 1:

Determine the specific volume:

p₁v₁ = RT₁

[tex]v_1 = \frac{R'T_1}{p_1} = \frac{(0.28699.\frac{kJ}{kg.K} )(300 k)}{(1.05 bar *\ \frac{10^5 N/m^2}{1 bar} *\frac{1kJ}{1000N.m} )} \\\\v_1 = 0.81997 \ m^3/kg[/tex]

Step 2:

determine the mass flow rate; m' = V / v₁

mass flow rate, m' = 0.65 / 0.81997

mass flow rate, m' = 0.7927 kg/s

Step 3:

using steam table, we determine enthalpy change;

h₁ at T₁ = 300.19 kJ /kg

h₂ at T₂ = 400.98 kJ/kg

Δh = h₂ - h₁

Δh = 400.98 - 300.19

Δh = 100.79 kJ/kg

step 4:

determine work input;

W = Q - mΔh

Where;

Q is heat transfer = - 6.5 kW, because heat is lost to surrounding

W = (-6.5) - (0.7927 x 100.79)

W = -6.5 -79.896

W = -86.396 kW

Therefore, the power input, in kW is -86.396 kW

Air as an ideal gas in a closed system undergoes a reversible process between temperatures of 1000 K and 400 K. The beginning pressure is 200 bar. Determinc the highest possible ending pressure for this process.If the ending pressure is 3 bar, determine the heat transfer and work per unit mass, if the boundary of the system is in constant contact with a reservoir at 400 K.

Answers

Answer:

highest possible ending pressure for this process is 8.0954 bar

Explanation:

We can say that Heat transfer is any or all of several kinds of phenomena, considered as mechanisms, that convey energy and entropy from one location to another. The specific mechanisms are usually referred to as convection, thermal radiation, and conduction.

Please see attachment for the solution.

Consider a drainage basin having 60% soil group A and 40% soil group B. Five years ago the land use pattern in the basin was ½ wooded area with poor cover and ½ cultivated land (row crops/contoured and terraces) with good conservation treatment. Now the land use has been changed to 1/3 wooded area with poor cover, 1/3 cultivated land (row crops/contoured and terraces) with good conservation treatment, and 1/3 commercial and business area.

(a) Estimate the increased runoff volume during the dormant season due to the land use change over the past 5-year period for a storm of 35 cm total depth under the dry antecedent moisture condition (AMC I). This storm depth corresponds to a duration of 6-hr and 100-year return period. The total 5-day antecedent rainfall amount is 30 mm. (Note: 1 in = 25.4 mm.)
(b) Under the present watershed land use pattern, find the effective rainfall hyetograph (in cm/hr) for the following storm event using SCS method under the dry antecedent moisture condition (AMC I).

Answers

Answer:

Please see the attached file for the complete answer.

Explanation:

A turbojet aircraft is flying with a velocity of 280 m/s at an altitude of 9150 m, where the ambient conditions are 32 kPa and -32C. The pressure ratio across the compressor is 12, and the temperature at the turbine inlet is 1100 K. Air enters the compressor at a rate of 50 kg/s, and the jet fuel has a heating value of 42,700 kJ/kg. Assume constant specific heats for air at room temperature. Efficiency of the compressor is 80%, efficiency of the turbine is 85%. Assume air leaves diffuser with negligibly small velocity.
determine
(a) The velocity of the exhaust gases.
(b) The rate of fuel consumption.

Answers

Answer:

(a) The velocity of the exhaust gases. is 832.7 m/s

(b) The rate of fuel consumption is 0.6243 kg/s

Explanation:

For the given turbojet engine operating on an ideal cycle, the pressure ,temperature, velocity, and specific enthalpy of air at [tex]i^{th}[/tex] state are [tex]P_i[/tex] , [tex]T_i[/tex] , [tex]V_i[/tex] , and [tex]h_i[/tex] , respectively.

Use "ideal-gas specific heats of various common gases" to find the properties of air at room temperature.

Specific heat at constant pressure, [tex]c_p[/tex] = 1.005 kJ/kg.K

Specific heat ratio, k = 1.4

A certain process requires 2.0 cfs of water to be delivered at a pressure of 30 psi. This water comes from a large-diameter supply main in which the pressure remains at 60 psi. If the galvanized iron pipe connecting the two locations is 200 ft long and contains six threaded 90o elbows, determine the pipe diameter. Elevation differences are negligible.

Answers

Answer:

determine the pipe diameter.  = 0.41ft

Explanation:

check the attached file for answer explanation

Answer: you need to do it on your own first

Explanation:

When your complex reaction time is compromised by alcohol, an impaired person's ability to respond to emergency or unanticipated situations is greatly______.

Answers

Answer:

decreased

Explanation:

when impaired you react slower then you would sober.

Final answer:

Alcohol adversely affects the complex reaction time, considerably decreasing the individual’s ability to respond swiftly and adequately in emergencies or unexpected situations. This impairment is attributed to alcohol's impact on the brain causing slow information processing, poor motor control, and a decrease in focus.

Explanation:

When a person's complex reaction time is compromised by alcohol, their ability to respond to unexpected situations or emergencies is greatly diminished. Alcohol's impact on the brain leads to slower processing of information, reduced concentration, and poorer motor control. As a result, they may not react as quickly or efficiently as they would if they were sober to changes in their environment. For example, if a situation arises that requires quick decision-making, such as stopping abruptly while driving to avoid a pedestrian, an intoxicated individual may not respond in time, leading to catastrophic outcomes.

Learn more about Alcohol impact on reaction time here:

https://brainly.com/question/1002220

#SPJ2

The vehicle motor or engine can be size based on required peak power. The energy or average power required provides a sense for how much fuel is required.

1. Calculate the average and peak power (kW) needed to accelerate a 1364 kg vehicle from 0 to 60 mph in 6 seconds. Assume that aerodynamic, rolling, and hill‐climbing force counts for an extra 10% of the needed acceleration force.
2. Chart the average and peak power (kW) vs. time duration from 2 to 15 seconds.
3. How much energy (kWh) is required to accelerate the vehicle?

Answers

Answer:

1. Parg = 89.954 kw

  Pmax = 179.908 kw

2. Parg = 29.984 kw

  Pmax = 59.96 kw

3. Energy = 0.15 kWh

Explanation:

See the attached file for the calculation

Answer:

1) P = 81.74 kW

2) As seen on the pic.

3) E = 0.1362 kWh

Explanation:

1) Given

m = 1364 kg (mass of the vehicle)

vi = 0 mph = 0 m/s  (initial speed)

vf = 60 mph = (60 mph)(1609 m/ 1 mi)(1 h/ 3600 s) = 26.8167 m/s  (final speed)

t = 6 s

We get the acceleration as follows

a = (vf - vi)/t  ⇒   a = (26.8167 m/s - 0 m/s)/ 6s

⇒   a = 4.469 m/s²

then the Force is

F = m*a ⇒   F = 1364 kg*4.469 m/s²

⇒   F = 6096.32 N

Then we get the average power as follows

P = F*v(avg) = F*(vi + vf)/2

⇒   P = 6096.32 N*(0 m/s + 26.8167 m/s)/2

⇒   P = 81741.59 W = 81.74 kW

Knowing that that aerodynamic, rolling, and hill‐climbing force counts for an extra 10% of the needed acceleration force, we use the following formula to find the peak power

Pmax = (1 + 0.1)*F*vf  = 1.1*F*vf

⇒   Pmax = 1.1*6096.32 N*26.8167 m/s

⇒   Pmax = 179831.503 W = 179.83 kW

2) The pic 1 shows the average and peak power (kW) vs. time duration from 2 to 15 seconds.

In the first chart we use the equation

Pinst = F*v  where F is constant and v is the instantaneous speed, and Pavg is the mean of the values.

In the second chart, we use the equation

Ppeak = 1.1*F*v  where F is constant and v is the instantaneous speed.

3) For 0 s ≤ t ≤ 6 s

We can use the equation

E = ΔK = Kf - Ki = 0.5*m*(vf² - vi²)

⇒   E = 0.5*1364 kg*((26.8167 m/s)² - (0 m/s)²)

⇒   E = 490449.123 J = (490449.123 J)(1 kWh/3.6*10⁶J)

⇒   E = 0.1362 kWh

A stream of moist air flows into an air conditioner with an initial humidity ratio of 0.6 kg(vapor)/kg(dry air), and a dry air flow rate of 1.5 kg/s. If the moist air stream mixes with a separate stream of water vapor at 0.4 kg/s, what will the humidity ratio be at the exit in kg(vapor)/kg(dry air)?

Answers

Answer:

[tex]\omega_{out} = 0.867\,\frac{kg\,H_{2}O}{kg\,DA}[/tex]

Explanation:

The final humidity ratio is computed by the Principle of Mass Conservation:

Dry Air

[tex]\dot m_{in} = \dot m_{out}[/tex]

Moist

[tex]\dot m_{in} \cdot \omega_{in} + \dot m_{w} = \dot m_{out}\cdot \omega_{out}[/tex]

Then, the final humidity ratio is:

[tex]\omega_{out} = \frac{\dot m_{in}\cdot \omega_{in}+\dot m_{w}}{\dot m_{out}}[/tex]

[tex]\omega_{out} = \omega_{in} + \frac{\dot m_{w}}{\dot m_{out}}[/tex]

[tex]\omega_{out} = 0.6\,\frac{kg\,H_{2}O}{kg\,DA} + \frac{0.4\,\frac{kg\,H_{2}O}{s} }{1.5\,\frac{kg\,DA}{s} }[/tex]

[tex]\omega_{out} = 0.867\,\frac{kg\,H_{2}O}{kg\,DA}[/tex]

The humidity ratio at the exit is approximately 0.87 kg(vapor)/kg(dry air) when moist air mixes with water vapor.

To solve this problem, we need to apply the conservation of mass principle for both the dry air and the water vapor.

Let's denote:

- [tex]\( w_{in} \)[/tex] as the initial humidity ratio of the moist air stream entering the air conditioner.

- [tex]\( \dot{m}_{dry} \)[/tex]  as the mass flow rate of the dry air stream.

- [tex]\( w_{water} \)[/tex]  as the humidity ratio of the separate stream of water vapor.

- [tex]\( \dot{m}_{water} \)[/tex] as the mass flow rate of the separate stream of water vapor.

- [tex]\( w_{out} \)[/tex] as the humidity ratio of the mixture at the exit.

According to the conservation of mass principle:

For dry air:

[tex]\[ \dot{m}_{dry} \times w_{in} = \dot{m}_{dry} \times w_{out} \][/tex]

For water vapor:

[tex]\[ \dot{m}_{water} \times w_{water} = \dot{m}_{dry} \times (w_{out} - w_{in}) \][/tex]

Given values:

- [tex]\( w_{in} = 0.6 \)[/tex] kg(vapor)/kg(dry air)

- [tex]\( \dot{m}_{dry} = 1.5 \)[/tex] kg/s

- [tex]\( w_{water} = 1 \) kg(vapor)/kg(dry air)[/tex] (since water vapor is pure, its humidity ratio is 1)

- [tex]\( \dot{m}_{water} = 0.4 \) kg/s[/tex]

Now, we can solve for [tex]\( w_{out} \)[/tex]:

From the first equation:

[tex]\[ w_{out} = \frac{\dot{m}_{dry} \times w_{in}}{\dot{m}_{dry}} = w_{in} = 0.6 \, \text{kg(vapor)/kg(dry air)} \][/tex]

Substitute this value into the second equation:

[tex]\[ \dot{m}_{water} \times w_{water} = \dot{m}_{dry} \times (w_{out} - w_{in}) \][/tex]

[tex]\[ 0.4 \times 1 = 1.5 \times (w_{out} - 0.6) \][/tex]

Now, solve for [tex]\( w_{out} \)[/tex]:

[tex]\[ 0.4 = 1.5 \times (w_{out} - 0.6) \][/tex]

[tex]\[ 0.4 = 1.5w_{out} - 0.9 \][/tex]

[tex]\[ 1.5w_{out} = 0.4 + 0.9 \][/tex]

[tex]\[ 1.5w_{out} = 1.3 \][/tex]

[tex]\[ w_{out} = \frac{1.3}{1.5} \][/tex]

[tex]\[ w_{out} \approx 0.87 \, \text{kg(vapor)/kg(dry air)} \][/tex]

So, the humidity ratio at the exit will be approximately 0.87 kg(vapor)/kg(dry air).

A system executes a power cycle while receiving 1000 kJ by heat transfer at a temperature of 500 K and discharging 700 kJ by heat transfer at a temperature of 300 K. There are no other heat transfers. Determine the cycle efficiency. Use the Clausius Inequality to determine , in kJ/K. Determine if this cycle is internally reversible, irreversible, or impossible.

Answers

Answer:

[tex]\eta_{th} = 30\,\%[/tex], [tex]\eta_{th,max} = 40\,\%[/tex], [tex]\Delta S = \frac{1}{3}\,\frac{kJ}{K}[/tex], The cycle is irreversible.

Explanation:

The real cycle efficiency is:

[tex]\eta_{th} = \frac{1000\,kJ-700\,kJ}{1000\,kJ} \times 100\,\%[/tex]

[tex]\eta_{th} = 30\,\%[/tex]

The theoretical cycle efficiency is:

[tex]\eta_{th,max} = \frac{500\,K-300\,K}{500\,K} \times 100\,\%[/tex]

[tex]\eta_{th,max} = 40\,\%[/tex]

The reversible and real versions of the power cycle are described by the Clausius Inequalty:

Reversible Unit

[tex]\frac{1000\,kJ - 600kJ}{300\,K}= 0[/tex]

Real Unit

[tex]\Delta S = \frac{1000\,kJ-600\,kJ}{300\,K} -\frac{1000\,kJ-700\,kJ}{300\,K}[/tex]

[tex]\Delta S = \frac{1}{3}\,\frac{kJ}{K}[/tex]

The cycle is irreversible.

The cycle efficiency using clausius inequality is;

σ_cycle = 0.333 kJ/kg and is internally irreversible

For the cycle, we know that efficiency is;

η = 1 - Q_c/Q_h

Thus;

Q_c = (1 - η)Q_h

Now, the cycle efficiency is derived from the integral;

σ_cycle = -∫(dQ/dt)ₐ

Thus; σ_cycle = -[(Q_h/T_h) - (Q_c/T_c)]

We are given;

Q_h = 1000 kJ

T_h = 500 k

T_c = 300 k

Q_c = 700 kJ

Thus;

σ_cycle = -[(1000/500) - (700/300)]

σ_cycle = -(2 - 2.333)

σ_cycle = 0.333 kJ/kg

Since σ_cycle > 0, then the cycle is internally irreversible

Read more about cycle efficiency at; https://brainly.com/question/16014998

Water flows at a rate of 0.040 m3 /s in a horizontal pipe whose diameter is reduced from 15 cm to 8 cm by a reducer. If the pressure at the centerline is measured to be 480 kPa and 440 kPa before and after the reducer, respectively, determine the irreversible head loss in the reducer. Take the kinetic energy correction factors to be 1.05. Answer: 0.963 m

Answers

Answer:

hL = 0.9627 m

Explanation:

Given

Q = 0.040 m³/s (constant value)

D₁ = 15 cm = 0.15 m  ⇒  R₁ = D₁/2 = 0.15 m/2 = 0.075 m

D₂ = 8 cm = 0.08 m  ⇒  R₂ = D₂/2 = 0.08 m/2 = 0.04 m

P₁ = 480 kPa = 480*10³Pa

P₂ = 440 kPa = 440*10³Pa

α = 1.05

ρ = 1000 Kg/m³

g = 9.81 m/s²

h₁ = h₂

hL = ?  (the irreversible head loss in the reducer)

Using the formula Q = v*A   ⇒  v = Q/A

we can find the velocities v₁ and v₂ as follows

v₁ = Q/A₁ = Q/(π*R₁²) = (0.040 m³/s)/(π*(0.075 m)²) = 2.2635 m/s

v₂ = Q/A₂ = Q/(π*R₂²) = (0.040 m³/s)/(π*(0.04 m)²) = 7.9577 m/s

Then we apply the Bernoulli law (for an incompressible flow)

(P₂/(ρ*g)) + (α*v₂²/(2*g)) + h₂ = (P₁/(ρ*g)) + (α*v₁²/(2*g)) + h₁ - hL

Since h₁ = h₂ we obtain

(P₂/(ρ*g)) + (α*v₂²/(2*g)) = (P₁/(ρ*g)) + (α*v₁²/(2*g)) - hL

⇒  hL = ((P₁-P₂)/(ρ*g)) + (α/(2*g))*(v₁²-v₂²)

⇒  hL = ((480*10³Pa-440*10³Pa)/(1000 Kg/m³*9.81 m/s²)) + (1.05/(2*9.81 m/s²))*((2.2635 m/s)²-(7.9577 m/s)²)

⇒  hL = 0.9627 m

An air-conditioning system is used to maintain a house at 70°F when the temperature outside is 100°F. The house is gaining heat through the walls and the windows at a rate of 800 Btu/min, and the heat generation rate within the house from people, lights, and appliances amounts to 100 Btu/min. Determine the minimum power input required for this air- conditioning system.

Answers

Answer:

Minimum power output required = 1.1977 hp

Explanation:

Given Data:

Temperature outside = 100°F.

House temperature =  70°F

Rate of heat gain(Qw) =  800 Btu/min

Generation rate within(Ql) = 100 Btu/min.

Converting the outside temperature 100°F from fahrenheit to ranking, we have;

1°F = 460R

Therefore,

100°F = 460+100

 To     = 560 R

Converting the house temperature 70°F from fahrenheit to ranking, we have;

1°F = 460R

Therefore,

70°F = 460+70

    Th      = 530 R

Consider the equation for coefficient of performance (COP) of refrigerator in terms of temperature;

COP =Th/(To-Th)

        = 530/(560-530)

        = 530/30

        = 17.66

Consider the equation for coefficient of performance (COP) of refrigerator;

COP = Desired output/required input

         =  Q/Wnet

          = Ql + Qw/ Wnet

Substituting into the formula, we have;

17.667 = (100 + 800)/Wnet

17.667 = 900/Wnet

Wnet = 900/17.667

         = 50.94 Btu/min.

Converting from Btu/min. to hp, we have;

1 hp = 42.53 Btu/min.

Therefore,

50.94 Btu/min =  50.94 / 42.53

                         = 1.1977 hp =

Therefore, minimum power output required = 1.1977 hp

Given the following data:

Outside temperature = 100°F.House temperature =  70°F.Rate of heat gain =  800 Btu/min.Heat generation rate = 100 Btu/min.

The conversion of temperature.

We would convert the value of the temperatures in Fahrenheit to Rankine.

Note: 1°F = 460R

Conversion:

Outside temperature = 100°F = [tex]460+100[/tex] = 560RHouse temperature =  70°F = [tex]460+70[/tex] = 530R

To calculate the minimum power input that is required for this air- conditioning system:

The coefficient of performance (COP)

In Science, the coefficient of performance (COP) is a mathematical expression that is used to show the relationship between the power output of an air-conditioning system and the power input of its compressor.

Mathematically, the coefficient of performance (COP) is given by the formula:

[tex]COP =\frac{T_h}{T_o-T_h}[/tex]

Substituting the given parameters into the formula, we have;

[tex]COP =\frac{530}{560-530}\\ \\ COP =\frac{530}{30}[/tex]

COP = 17.66

For the power input:

[tex]COP = \frac{E_o}{E_i} \\ \\ COP = \frac{Q_l + Q_w}{Q_{net}}\\ \\ 17.67 = \frac{100+800}{Q_{net}}\\ \\ Q_{net}=\frac{900}{17.67} \\ \\ Q_{net}=50.93\;Btu/min[/tex]

Conversion:

1 hp = 42.53 Btu/min.

X hp = 50.93 Btu/min.

Cross-multiplying, we have:

[tex]X=\frac{50.93}{42.53} [/tex]

X = 1.1975 hp

Read more on power input here: https://brainly.com/question/16188638

A novel gaseous hydrocarbon fuel CxHy is proposed for use in spark-ignition engines. An analysis of a sample of this fuel revealed that its molecular weight is 140 and its molar H/C ratio is 2.0. In order to evaluate some of its properties, the fuel was burned with stoichiometric standard air in a constant pressure, steady-flow reactor. The fuel and air entered the reactor at 25°C, and the products of complete combustion were cooled to 25°C. At the exit condition, water in the products was a liquid. It was measured that the heat given off during the process to the cooling system of the reaction was 47.5 MJ/kg of fuel. a) Determine the fuel formula. b) What does that heat given-off to the cooling system of the reactor represent? c) Determine the lower heating value of the fuel. d) Determine the enthalpy of formation of the fuel at 25°C

Answers

Answer:

(a) Fuel formula = C₁₀H₂₀

(b)The reactor represent higher heating value (HHV) of the fuel because the water in the product is liquid.

(c) Lower heating value = 44.36 mj/kg

(d) - 6669.8 KJ/Kmol

Explanation:

See the attached files for the calculation

Locate the centroid y¯ of the composite area. Express your answer to three significant figures and include the appropriate units. y¯ = nothing nothing Request Answer Part B Determine the moment of intertia of this area about the centroidal x′ axis. Express your answer to three significant figures and include the appropriate units. Ix′ = nothing nothing Request Answer Provide Feedback

Answers

Answer:

Please see the attached Picture for the complete answer.

Explanation:

Five Kilograms of continuous boron fibers are introduced in a unidirectional orientation into of an 8kg aluminum matrix. Calculate:

a. the density of the composite.
b. the modulus of elasticity parallel to the fibers.
c. the modulus of elasticity perpendicular to the fibers.

Answers

Answer:

Explanation:

Given that,

Mass of boron fiber in unidirectional orientation

Mb = 5kg = 5000g

Mass of aluminum fiber in unidirectional orientation

Ma = 8kg = 8000g

A. Density of the composite

Applying rule of mixing

ρc = 1•ρ1 + 2•ρ2

Where

ρc = density of composite

1 = Volume fraction of Boron

ρ1 = density composite of Boron

2 = Volume fraction of Aluminum

ρ2 = density composite of Aluminum

ρ1 = 2.36 g/cm³ constant

ρ2 = 2.7 g/cm³ constant

To Calculate fractional volume of Boron

1 = Vb / ( Vb + Va)

Vb = Volume of boron

Va = Volume of aluminium

Also

To Calculate fraction volume of aluminum

2= Va / ( Vb + Va)

So, we need to get Va and Vb

From density formula

density = mass / Volume

ρ1 = Mb / Vb

Vb = Mb / ρ1

Vb = 5000 / 2.36

Vb = 2118.64 cm³

Also ρ2 = Ma / Va

Va = Ma / ρ2

Va = 8000 / 2.7

Va = 2962.96 cm³

So,

1 = Vb / ( Vb + Va)

1 = 2118.64 / ( 2118.64 + 2962.96)

1 = 0.417

Also,

2= Va / ( Vb + Va)

2 = 2962.96 / ( 2118.64 + 2962.96)

2 = 0.583

Then, we have all the data needed

ρc = 1•ρ1 + 2•ρ2

ρc = 0.417 × 2.36 + 0.583 × 2.7

ρc = 2.56 g/cm³

The density of the composite is 2.56g/cm³

B. Modulus of elasticity parallel to the fibers

Modulus of elasticity is defined at the ratio of shear stress to shear strain

The relation for modulus of elasticity is given as

Ec = = 1•Eb+ 2•Ea

Ea = Elasticity of aluminium

Eb = Elasticity of Boron

Ec = Modulus of elasticity parallel to the fiber

Where modulus of elastic of aluminum is

Ea = 69 × 10³ MPa

Modulus of elastic of boron is

Eb = 450 × 10³ Mpa

Then,

Ec = = 1•Eb+ 2•Ea

Ec = 0.417 × 450 × 10³ + 0.583 × 69 × 10³

Ec = 227.877 × 10³ MPa

Ec ≈ 228 × 10³ MPa

The Modulus of elasticity parallel to the fiber is 227.877 × 10³MPa

OR Ec = 227.877 GPa

Ec ≈ 228GPa

C. modulus of elasticity perpendicular to the fibers?

The relation of modulus of elasticity perpendicular to the fibers is

1 / Ec = 1 / Eb+ 2 / Ea

1 / Ec = 0.417 / 450 × 10³ + 0.583 / 69 × 10³

1 / Ec = 9.267 × 10^-7 + 8.449 ×10^-6

1 / Ec = 9.376 × 10^-6

Taking reciprocal

Ec = 106.66 × 10^3 Mpa

Ec ≈ 107 × 10^3 MPa

Note that the unit of Modulus has been in MPa,

7. Implement a function factorial in RISC-V that has a single integer parameter n and returns n!. A stub of this function can be found in the file factorial.s. You will only need to add instructions under the factorial label, and the argument that is passed into the function is configured to be located at the label n. You may solve this problem using either recursion or iteration

Answers

Answer:

addi x31, x0, 4

addi x30, x0, 2

Explanation:

Recursion in computer sciencs is defined as a method of solving a problem in which the solution to the problem depends on solutions to smaller cases of the same problem. Such problems can generally be solved by iteration, but this needs to identify and index the smaller cases at time of programming.

addi x31, x0, 4

addi x30, x0, 2

addi x2, x0, 1600 // initialize the stack to 1600, x2= stackpointer

ecall x5, x0, 5 // read the input to x5

jal x1, rec_func

ecall x0, x10, 2 // print the result now

beq x0, x0, end

rec_func:

addi x2, x2, -8 // make room in stack

sd x1, 0(x2) // store pointer and result in stack

bge x5, x31, true // if i > 3, then go to true branch

ld x1, 0(x2)

addi x10, x0, 1 // if i <= 3, then return 1

addi x2, x2, 8 // reset stack point

jalr x0, 0(x1)

true:

addi x5, x5, -2 // compute i-2

jal x1, rec_func // call recursive func for i-2

ld x1, 0(x2) // load the return address

addi x2, x2, 8 // reset stack point

mul x10, x10, x30 // multiply by 2

addi x10, x10, 1 // add 1

jalr x0, 0(x1) // return

end:

A preheater involves the use of condensing steam at 100o C on the inside of a bank of tubes to heat air that enters at I atm and 25o C. The air moves at 5 m/s in cross flow over the tubes. Each tube is 1 m long and has an outside diameter of 10 mm. The bank consists of 196 tubes in a square, aligned array for which ST = SL = 15 mm. What is the total rate of heat transfer to the air? What is the pressure drop associated with the airflow?

(b) Repeat the analysis of part (a), but assume that the tubes have a staggered arrangement with ST = 15 mm and SL = 10 mm.

Answers

Answer:

Please see the attached file for the complete answer.

Explanation:

The elastic settlement of an isolated single pile under a working load similar to that of piles in the group it represents, is predicted to be 0.25 inches. What is the expected settlement for the pile group given the following information?

1.Group: 16 piles in a 4x4 group
2.Pile Diameter: 12 inches
3.Pile Center to Center Spacing: 3 feet

Answers

Answer:

The expected settlement for the pile group using the given information is 19.92mm or 0.79 inch

Explanation:

In this question, we are asked to calculate the expected settlement for the pole group given some information.

Please check attachment for complete solution and step by step explanation

The diffusion of a molecule in a tissue is studied by measuring the uptake of labeled protein into the tissue of thickness L =8 um. Initially, there is no labeled protein in the tissue. At t=0, the tissue is placed in a solution with a molecular concentration of C1=9.4 uM, so the surface concentration at x=0 is maintained at C1. Assume the tissue can be treated as a semi-infinite medium. Surface area of the tissue is A = 4.2 cm2. Calculate the flux into the tissue at x=0 and t=5 s.Please give your answer with a unit of umol/cm2 s. Assuming the diffusion coefficient is known of D=1*10-9 cm2/s

Answers

Answer:

The flux into the tissue at x=0 and t=5 s is 0.4476 uM/cm²s

Explanation:

Flux = [tex]\frac{Quantity}{Area * Time}[/tex]

given:

Area = 4.2 cm²

Time = 5 sec

Quantity ( concentration) = 9.4 uM

∴ Flux = Quantity / (Area × Time)

Flux = 9.4 uM / (4.2 cm² × 5 s)

Flux = 9.4 uM / 21 cm²s

Flux = 0.4476 uM/cm²s

10. Develop a logic circuit called "Simple Multiples." This circuit accepts 4 bits that represent a BCD number. It has three outputs:

• A HIGH on output X indicates that the number is a multiple of 2
• A HIGH on output Y indicates that the number is a multiple of 3
• A HIGH on output Z indicates that the number is a multiple of both 2 and 3 *0 counts as a multiple for all of these

Create a truth table for this circuit

Answers

Answer:

Explanation:

"Simple Multiples Logic Circuit Development"

From the attached file below;

The first diagram illustrate the truth table. The input consist of binary coded decimal with  its 16  possible output. As stated in the input, assuming we have 0010 which the value is 2, thus ; it is said to be divisible by 2 , then we enter the output of x  to be 1 and the remaining as zeros

The second diagram talks about the output x; the representation of x is 1 there and it was added up. The use case employed is  [tex]x + \bar {x} =1[/tex] which in turn yield output [tex]\bar {A3}[/tex]

The second to the last diagram represents output Y and Z.

As output Y can be further disintegrated ; we insert XNOR gate for the expressions. The expression is  [tex]a.b+(\bar{a}. \bar{b})[/tex]

The last diagram is the logic diagram.

A PMDC machine is measured to va120Vdc, ia 5.5A at the electrical terminals and the shaft is measured to have Tmech 5.5Nm, ns1200RPM. State whether the machine acting as a motor or a generator and state the efficiency of the system. Q11. Motor, 89.4 %(a) Generator, 89.4%(b) Motor, 95.5%(c) Generator, 95.5 %(d) none of the abov

Answers

Answer:

(c) Generator, 95.5 %

Explanation:

given data

voltage va = 120V

current Ia = - 5.5 A

Tmech =  5.5Nm

ns = 1200 RPM

solution

first we get here electric input power that is express as

electric input power = va × Ia    ......1

put here value and we get

electric input power = 120 × -5-5

electric input power -660 W

here negative mean it generate power

and here

Pin ( mech) will be

Pin ( mech) = Tl × ω   .........2

Pin ( mech) = 5.5 × [tex]\frac{2\pi N}{60}[/tex]    

Pin ( mech) =  5.5 × [tex]\frac{2\pi 1200}{60}[/tex]  

Pin ( mech) = 691.150 W

and

efficiency will be here as

efficiency = [tex]\frac{660}{691.150}[/tex]    

efficiency = 95.5 %

so correct option is (c) Generator, 95.5 %

The steel bar has a 20 x 10 mm rectangular cross section and is welded along section a-a. The weld material has a tensile yield strength of 325 MPa and a shear yield strength of 200 MPa, and the bar material has a tensile yield strength of 350 MPa. An overall factor of safety of at least 2.0 is required. Find the largest load P that can be applied, to satisfy all criteria.

Answers

Final answer:

The largest load P that can be applied to the steel bar, ensuring a factor of safety of 2.0 with respect to the weld material's tensile yield strength, is 32.5 kN. This is calculated based on the allowable tensile strength of the weld after applying the factor of safety and the cross-sectional area of the steel bar.

Explanation:

The student's question relates to the structural engineering concept of material strength and loading. The maximum load P that can be safely applied to a welded steel bar can be determined by considering the tensile and shear yield strengths of the two materials involved, i.e., the weld material and the bar material. Using the given factor of safety of 2.0, the tensile strength of the weld and the bar, and the cross section of the bar, we can calculate the allowable tensile stress and then the maximum load P by dividing the allowable tensile stress by the area of the cross section.

To begin with, we find the allowable tensile strength by dividing the weld material's yield strength (which is the weaker material concerning tensile strength) by the factor of safety:

Allowable tensile strength for weld = 325 MPa / 2 = 162.5 MPa

Next, we need to calculate the area of the cross-section of the bar:

Area (A) = 20 mm x 10 mm = 200 mm² = 200 x 10⁻⁶ m²

Now, we convert the units of the allowable tensile strength to N/m² (because 1 MPa = 1 x 10⁶ N/m²) and calculate the maximum tensile load (Ptensile) that the weld can sustain:

Allowable tensile strength for weld in N/m² = 162.5 x 10⁶ N/m²Ptensile = Allowable tensile strength for weld x AreaPtensile = (162.5 x 10⁶ N/m²) x (200 x 10⁻⁶ m²)Ptensile = 32.5 x 10³ N = 32.5 kN

Thus, the largest load P that can be applied to the steel bar to satisfy the safety criteria is 32.5 kN.

A 36 ft simply supported beam is loaded with concentrated loads 16 ft inwards from each support. On the left side, the dead load is 8.0 kips and the live load is 18.0 kips. On the other side, the dead load is 4.0 kips and the live load is 9.0 kips. Self-weight of the beam can be ignored. Lateral supports are provided at the supports and the load points. Determine the least-weight W-shape to carry the load. Use A992 steel, Cb = 1.0 and Table 3.10 of the 15th edition of the Manual. check if a W21×62 will be sufficient considering the correct Cb. Do not use Table 3.10 and work the problem with calculations.

Answers

Answer:

1st part: Section W18X76  is adequate

2nd part: Section W21X62 is adequate

Explanation:

See the attached file for the calculation

A pump is used to deliver water from a lake to an elevated storage tank. The pipe network consists of 1,800 ft (equivalent length) of 8-in. pipe (Hazen-Williams roughness coefficient = 120). Ignore minor losses. The pump discharge rate is 600 gpm. The friction loss (ft) is most nearly Group of answer choicesA. 15
B. 33
C. 106
D. 135

Answers

Answer:

h_f = 15 ft, so option A is correct

Explanation:

The formula for head loss is given by;

h_f = [10.44•L•Q^(1.85)]/(C^(1.85))•D^(4.8655))

Where;

h_f is head loss due to friction in ft

L is length of pipe in ft

Q is flow rate of water in gpm

C is hazen Williams constant

D is diameter of pipe in inches

We are given;

L = 1,800 ft

Q = 600 gpm

C = 120

D = 8 inches

So, plugging in these values into the equation, we have;

h_f = [10.44*1800*600^(1.85)]/(120^(1.85))*8^(4.8655))

h_f = 14.896 ft.

So, h_f is approximately 15 ft

Air is compressed from 100 kPa, 300 K to 1000 kPa in a two-stage compressor with intercooling between stages. The intercooler pressure is 300 kPa. The air is cooled back to 300 K in the intercooler before entering the second compressor stage. Each compressor stage is isentropic. Please calculate the total compressor work per unit of mass flow (kJ/kg). Repeat for a single stage of isentropic compression from the given inlet to the final pressure.

Answers

Answer:

The total compressor work is 234.8 kJ/kg for a isentropic compression

Explanation:

Please look at the solution in the attached Word file

Final answer:

The total compressor work per unit of mass flow in a two-stage compressor with intercooling can be calculated by summing the compressor work in each stage and the work done in the intercooler.

Explanation:

The total compressor work per unit of mass flow in a two-stage compressor with intercooling can be calculated by summing the compressor work in each stage and the work done in the intercooler.

In the first stage, the air is compressed from 100 kPa to 300 kPa. The work done in this stage can be calculated using the isentropic compression process. In the second stage, the air is further compressed from 300 kPa to 1000 kPa. The work done in this stage can also be calculated using the isentropic compression process.

To calculate the total compressor work per unit of mass flow, you need to sum the work done in each stage and the work done in the intercooler.

Consider an aluminum step shaft. The area of section AB and BC as well as CD are 0.1 inch2 , 0.15 inch 2 and 0.20 inch2. The length of section AB, BC and CD are 10 inch, 12 inch and 16 inch. A force F=1000 lbf is applied to B. The initial gap between D and rigid wall is 0.002. Using analytical approach, determine the wall reactions, the internal forces in members, and the displacement of B and C. Find the strain in AB, BC and CD.

Answers

Answer:

Explanation:

Find attach the solution

I have a signal that is experiencing 60 Hz line noise from a nearby piece of equipment, and I want to make sure that the noise is filtered out. I expect that there might be useful information at frequencies higher and lower than 60 Hz. Which would be the best type of filter for this purpose?

a. BandStop filter
b. Low-pass filter
c. Bandpass filter
d. High-pass filter

Answers

Answer:

a. BandStop filter

Explanation:

A band-stop filter or band-rejection filter is a filter that eliminates at its output all the signals that have a frequency between a lower cutoff frequency and a higher cutoff frequency. They can be implemented in various ways.  One of them is to implement a notch filter, which is characterized by rejecting a certain frequency that is interfering with a circuit. The transfer function of this filter is given by:

[tex]H(s)=\frac{s^2+\omega_o^2}{s^2+\omega_cs+\omega_o^2} \\\\Where:\\\\\omega_o=Central\hspace{3} rejected\hspace{3} frequency\\\omega_c=Width\hspace{3} of\hspace{3} the\hspace{3} rejected\hspace{3} band[/tex]

I attached you a graph in which you can see how the filter works.

Steel (AISI 1010) plates of thickness δ = 6 mm and length L = 1 m on a side are conveyed from a heat treatment process and are concurrently cooled by atmospheric air of velocity u[infinity] = 10 m/s and T[infinity] = 20°C in parallel flow over the plates. For an initial plate temperature of Ti = 300°C, what is the rate of heat transfer from the plate? What is the corresponding rate of change of the plate temperature? The velocity of the air is much larger than that of the plate.

Answers

Answer:

Rate of heat transfer from plate

6796.16 W

Corresponding rate of change of plate temperature

-2634 degrees.Celcius/sec

Explanation:

In this question, we are asked to calculate the rate of heat transfer and the corresponding rate of change of the plate temperature.

Please check attachment for complete solution and step by step explanation

Other Questions
A bag has 2 blue marbles 3 red marbles and 5 white marbles. Which event has a probability greater than 1/5 select three options Explain the benefits of STEM cell therapy. Be specific with examples and give a pretty brief reason. Wave action creates and changes beaches drastically. The sand that makes up beaches is transported along the shoreline by the following wave action. Waves typically approach shorelines at an angle rather than head on. Waves that hit the shoreline are then refracted perpendicular to the shoreline. The change in direction of a wave once it hits the shoreline transports sand grains along the shore. Water flow along shorelines is described with the following terms. Longshore drift is the net flow of water along the shore that results from waves that refract along the shoreline. Longshore drift is parallel to the shoreline in one direction. The direction roughly points towards the same general direction as sand transport and incoming waves. Upstream refers to the direction opposite of longshore drift. Rip currents are strong surface currents. Water that refracts from the shoreline can return out to sea along the surface or along the ocean bottom. Rip currents are the retreating waves that return along the surface. This type of current can be very dangerous to unwary swimmers. The dollar-value LIFO method was adopted by Blue Corp. on January 1, 2020. Its inventory on that date was $390,700. On December 31, 2020, the inventory at prices existing on that date amounted to $369,600. The price level at January 1, 2020, was 100, and the price level at December 31, 2020, was 112. How did word of the Holocaust spread beyond Germany, and how did people in other countries react to the news? 8 WILL GIVE BRAINLIEST *Which value is the solution of the equation 8.25r=554.4? Iron(III) oxide and hydrogen react to form iron and water, like this: Fe_2O_3(s) + 3H_2(g) rightarrow 2Fe(s) + 3H_2O(g) At a certain temperature, a chemist finds that a 5.4 L reaction vessel containing a mixture of iron(III) oxide, hydrogen, iron, and water at equilibrium has the following composition: Calculate the value of the equilibrium constant K_c for this reaction. Round your answer to 2 significant digits. Given the following information, formulate an inventory management system. The item is demanded 50 weeks a year. Item cost $ 8.00 Standard deviation of weekly demand 20 per week Order cost $ 207.00 Lead time 3 week(s) Annual holding cost (%) 24 % of item cost Service probability 99 % Annual demand 27,400 Average demand 548 per week a. Determine the order quantity and reorder point. What is the median value of the data set shown on the line plot?Enter your answer in the box. If you place a 29-foot ladder against the top of a 20-foot building, how many feet will the bottom of the ladder be from the bottom of the building? Sammy and his family took a hiking trip to the mountains. They started out with 20 pounds of food. They plan on eating 4 pounds of food each day. Write a. Equation that relates the remaining food supply r to the number d Which statement about histograms is true?A. Data is organized in categories.B. Data appears as bars that are all about the same height.C. Data is organized in equal intervals.D. Data appears as bars that do not touch. There appears to be a lack of faculty diversity. White Americans make up 79 percent of all full-time faculty members, as compared with _____ percent of African Americans, 4.2 percent of Hispanic Americans, and 0.5 percent of Native Americans. Englert Hospital began using standards to evaluate its Admissions Department. The standard was broken into two types of admissions as follows: Type of Admission Standard Time to Complete Admission Record Unscheduled admission 30 min. Scheduled admission 15 min. The unscheduled admission took longer because name, address, and insurance information needed to be determined and verified at the time of admission. Information was collected on scheduled admissions prior to the admissions, which was less time-consuming. The Admissions Department employs four full-time people (40 productive hours per week, with no overtime) at $15 per hour. For the most recent week, the department handled 140 unscheduled and 350 scheduled admissions. a. How much was actually spent on labor for the week? $ b. What are the standard hours for the actual volume for the week (round to one decimal place)? hours c. Calculate the time variance. Enter a favorable variance as a negative number using a minus sign and an unfavorable variance as a positive number. In your computation, round the standard direct labor rate to the nearest whole cent. Time variance $ 27/45=_/5?2/6=_/3?jjjjjj A collar is established by buying a share of stock for $50, buying a 6-month put option with exercise price $43, and writing a 6-month call option with exercise price $57. On the basis of the volatility of the stock, you calculate that for a strike price of $43 and expiration of 6 months, N(d1) = 0.8235, whereas for the exercise price of $57, N(d1) = 0.7411. a. What will be the gain or loss on the collar if the stock price increases by $1? Sharon weighs 145 pounds and has tried to lose 15 pounds since 10th grade. She loses the weight without too much effort but then over the next few months she returns to her original weight. This would support which obesity theory? A grocery chain conducted a random survey to determine the favorite flavor of a new potato crisp. The results are shown on the table. Which flavor is LEAST LIKELY to sell if stocked by the grocery chain?A)Ranch Crisps3/25B)Salsa Crisps7/20C)Cheese Crisps7/25D)Barbecue Crisps Kelly has always used "Password" as her password on her online accounts, Why should she change this? Check all thatPasswords should be used only onceit could be easily guessedPasswords must be uniqueIt contains insufficient personal informationPasswords should be changed regularly This action is an illustration of which presidential role?A) Commander-in-Chief of the Armed ForcesB) representative of the nationC) chief agenda setterD) chief executive