Compute the loss of head and pressure drop in 200 ft of horizontal 6-in diameter asphalted cast iron pipe carrying water with a mean velocity of 6 ft/s. For water: rho = 1.94 slug/ft3 and μ = 2.09x10-5 slug/ft-s (ν = μ/rho). Assume ε = 0.0004 ft.

Answers

Answer 1

Answer:

The answer is below

Step-by-step explanation:

12 inches = 1 ft.

6 inches = 6 inches * (1 ft./12 inches) = 0.5 ft.

Therefore the diameter of the cast iron (D) = 6 inches = 0.5 ft.

The area of cast iron (A) = πD²/4 = π(0.5)²/4 = 0.196 ft²

The velocity (V) = 6 ft./s, the acceleration due to gravity (g) = 32.2 ft./s²

ε/D = 0.0004 ft./ 0.5 ft. = 0.0008

Using the moody chart, find the line ε/D = 0.0008 and determine the point of intersection with the vertical line R = 2.7 * 10⁵. Hence we get f = 0.02.

The head loss (h) is:

[tex]h_f=f*\frac{L}{d}* \frac{V^2}{2g}=0.02*\frac{200\ ft}{0.5\ ft} *\frac{(6\ ft/s)^2}{2*32.2\ ft/s^2}=4.5\ ft[/tex]

The pressure drop (Δp) is:

Δp = ρg[tex]h_f[/tex] = [tex](62.4\ lbf/ft^3)(4.5\ ft)= 280\ lbf/ft^2[/tex]


Related Questions

When a number is decreased by 40% of itself the result is 96. What is the number?

Answers

Answer:

160

Step-by-step explanation:

96 / (100%-40%) = 96/ (60%)

= 96/0.6 = 160

Q) 96/(100% - 40%)

→ 96/ 60%

→ 96/ 0.6

→ 160 is the number.

bill took a nap for 1 1/4 hour on friday and then took a nap for 3/4 hour on tuesday. how much longer was Bill's nap on friday?

Answers

1/2 (2/4) of an hour longer. If you take 1 1/4 and subtract 3/4 you get 2/4=1/2
Answer: 30 minutes aka half an hour

Explanation: 1 1/4 hours in minutes = 75 min, 3/4 hours = 45 minutes so 75-45=30


If 80 persons can perform a piece of work in 16 days of 10 hours each, how
many men will perform a piece of work twice as great in tenth part of the time
working 8 hours a day supposing that three of the second set can do as much
work as four of the first set?

Answers

Answer:

The number of men needed to perform a piece of work twice as great in tenth part of the time  working 8 hours a day supposing that three of the second set can do as much  work as four of the first set is:

1200 men.

Step-by-step explanation:

To find the answer, first, we're gonna find how many hours take to make the piece of work in 16 days, taking into account each day just has 10 hours:

Number of hours to make a piece of work = 16 * 10 hoursNumber of hours to make a piece of work = 160 hours.

Now, we divide the total hours among the number of persons:

Equivalence of hours per person = 160 hours / 80 persons.Equivalence of hours per person = 2 hours /person

This equivalence isn't the real work of each person, we only need this value to make the next calculations. Now, we have a piece of work twice as great as the first, then, we can calculate the hours the piece of work needs to perform it (twice!):

Number of hours to make the second piece of work = 160 hours * 2Number of hours to make the second piece of work = 320 hours

We need to make this work in tenth part of the time working 8 hours a day, it means:

Time used to the second work = 320 hours / 10Time used to the second work = 32 hours Time used to the second work = 32 hours / 8 hours (as each day has 8 hours)Time used to the second work = 4 days

Now, we know three of the second set can do as much  work as four of the first set, taking into account the calculated equivalence, we have:

Work of four workers of first set = Work of three workers of second setWork of four workers of first set = Equivalence * 4 persons.Work of four workers of first set = 2 hours /person * 4 personsWork of four workers of first set = 8 hours.

So, three persons of the second set can make a equivalence of 8 hours. At last, we calculate all the number of workers we need in a regular time:

Number of needed workers in a regular time = (320 hours / 8 hours) * 3 persons.Number of needed workers in a regular time = 40 * 3 personsNumber of needed workers in a regular time = 120 persons

Remember we need to perform the job not in a regular time, we need to perform it in tenth part of the time, by this reason, we need 10 times the number of people:

Number of needed workers in tenth part of the time = 120 persons * 10Number of needed workers in tenth part of the time = 1200 persons

With this calculations, you can find the number of men needed to perform a piece of work twice as great in tenth part of the time  working 8 hours a day supposing that three of the second set can do as much  work as four of the first set is 1200 persons.

I will love and rate 5.0 if done correctly with no images and no trolling for answer.

A hardware store receives shipments containing 600 light bulbs each. A sample of 75 light bulbs in a given shipment contains 3 that are defective. What is the sample ratio of defective light bulbs to total light bulbs in the shipment written as a percent?

A - 4%
B - 10%
C - 20%
D - 76%

Answers

The correct answer should 4% because the ratio is 3 out of 75 which would leave 72 non-defective bulbs. So your answer is 4%

In the year 2000, the average car had a fuel economy of 22.6 MPG. You are curious as to whether the average in the present day is less than the historical value. What are the appropriate hypotheses for this test

Answers

Answer:

The appropriate null hypothesis is [tex]H_0: \mu = 22.6[/tex]

The appropriate alternative hypothesis is [tex]H_1: \mu < 22.6[/tex]

Step-by-step explanation:

The average car had a fuel economy of 22.6 MPG. Test if the current average is less than this.

At the null hypothesis, we test if the current average is still of 22.6 MPG, that is:

[tex]H_0: \mu = 22.6[/tex]

At the alternative hypothesis, we test if the current mean has decreased, that is, if it is less than 22.6 MPG. So

[tex]H_1: \mu < 22.6[/tex]

The manager of The Cheesecake Factory in Boston reports that on six randomly selected weekdays, the number of customers served was 175, 125, 180, 220, 240, and 245. She believes that the number of customers served on weekdays follows a normal distribution. Construct the 99% confidence interval for the average number of customers served on weekdays.

Answers

Answer:

(121.576 ; 273.424)

Step-by-step explanation:

Given the data:

175, 125, 180, 220, 240, 245

We can calculate the mean and standard deviation

Mean = Σx/ n = 1185 / 6 = 197.5

Standard deviation = 46.125 (calculator)

The confidence interval :

Mean ± margin of error

Margin of Error = Tcritical * s/sqrt(n)

Tcritical at 99%, df = n - 1 ; 6 - 1 = 5

Tcritical = 4.032

Margin of Error = 4.032 * 46.125/√6

Margin of error = 75.924

Confidence interval :

197.5 ± 75.924

Lower boundary = 197.5 - 75.924 = 121.576

Upper boundary = 197.5 + 75.924 = 273.424

(121.576 ; 273.424)

which of these tables represents a function

Answers

Answer: choice D

Step-by-step explanation:

In order for something to be a function for every x input there must be exactly 1 y output. This means that if x is a number then y must always be 1 number and that 1 number only.

What is the measure of n?

Answers

Answer:

n = √108 or 6√3

Step-by-step explanation:

n is the altitude of the right triangle

Based on the right triangle altitude theorem, we would have:

h = √(xy)

Where,

h = n

x = 18

y = 6

Substitute

n = √(18*6)

n = √108

Or

n = 6√3

Help me out thankssssss !!!!!!

Answers

Answer:

78/2=39°

Step-by-step explanation:

thx for the points

PLSSSSSS HELP ASAP !!!

Answers

Answer:

m4+m5=180

answer is second option

Can I have help I am stuck on this problem It would mean the world if u helped me and tysm!! =-)

Answers

Answer: yes yes no yes yes no

Step-by-step explanation:

Please help me with this question

Answers

Answer:

B

Step-by-step explanation:

In a boxplot, when the median is in the middle of the box, or when there are equal proportions around the median, the distribution is symmetric. As is shown here, the median is closer to the left side of the box, making it positively skewed (the mean is greater than the median) and not symmetric.

What is the answer for this question?

Answers

Answer:

The answer is A 1 4/5

Work:

7 1/5- 6 2/5

turn 7 1/5 into 6 6/5 and now subtract the two fractions

6/5-2/5= 4/5

now subtract the whole numbers:

6-6=1

So, your answer should be 4/5 (A)

The volume of a particular die is 6000 mm. Use the fact that 10 mm equals 1 cm to convert this
volume to cm.​

Answers

Answer:

600 cm³

Step-by-step explanation:

6000 mm/10 mm = 600 cm

Someone please answer yes I give brainliest​

Answers

slope is y2-y1 over x2-x1 so it is (5-9/0-4)

What is the area??!??

Answers

Answer:

142.7 m²

Step-by-step explanation:

but sure, what you know about triangles and trigonometry (simplified, the relationship of angles and sides of shapes based on circles enclosing them)

so, here a quick summary of important facts and angle/side relationships in triangles :

the sum of all angles in a triangle is always and for every triangle 180 degrees.

sin(angle) is vertically up or down from the horizontal diameter of the encircling circle to the point on the circle hit by a line from the center of the circle with the described angle from the horizontal diameter.

cos(angle) is horizontally left or right from the center of the encircling circle to the point, where the sine-line hits the horizontal diameter.

the sides are named in relation to their opposing corners and their angles. so, for example, side a is opposing the corner point A and the angle at this point (also called A).

here it is also important to know :

a/sin(A) = b/sin(B) = c/sin(C)

and the area of a general triangle is

area = 1/2 × b × c × sin(A) or

1/2 × a × c × sin(B) or

1/2 × a × b × sin(C)

so, if we want to use the first option, we need to calculate b first. for this we use

b/sin(B) = c/sin(C)

b = (c × sin(B)) / sin(C)

for this we need to calculate C first. and we use

A + B + C = 180

C = 180 - A - B = 180 - 54.3 - 30.4 = 95.3 degrees

=>

b = (26.3 × sin(30.4)) / sin(95.3) = 13.36583...

=> area = 1/2 × 13.36583... × 26.3 × sin(54.3) = 142.7324...

= 142.7 (rounded)

If the weight (in grams) of cereal in a box of Lucky Charms is N(489,6), what is the probability that the box will contain less than the advertised weight of 466 g

Answers

Answer:

0.000064 = 0.0064% probability that the box will contain less than the advertised weight of 466 g.

Step-by-step explanation:

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

N(489,6)

This means that [tex]\mu = 489, \sigma = 6[/tex]

What is the probability that the box will contain less than the advertised weight of 466 g?

This is the p-value of Z when X = 466. So

[tex]Z = \frac{X - \mu}{\sigma}[/tex]

[tex]Z = \frac{466 - 489}{6}[/tex]

[tex]Z = -3.83[/tex]

[tex]Z = -3.83[/tex] has a p-value of 0.000064

0.000064 = 0.0064% probability that the box will contain less than the advertised weight of 466 g.

HELP PLSSS I WILL GIVE THE FIRST PERSON TO ANSWER BRAINLYIST IF THERE RIGHT
i suck at math its easy

Answers

Option B and D are the correct answers

Answer:

A and B I guess so

can you find the limits of this ​

Answers

Answer:

[tex]\displaystyle \lim_{x \to -2} \frac{x^3 + 8}{x^4 - 16} = \frac{-3}{8}[/tex]

General Formulas and Concepts:

Calculus

Limits

Limit Rule [Constant]:                                                                                             [tex]\displaystyle \lim_{x \to c} b = b[/tex]

Limit Rule [Variable Direct Substitution]:                                                             [tex]\displaystyle \lim_{x \to c} x = c[/tex]

Limit Property [Addition/Subtraction]:                                                                   [tex]\displaystyle \lim_{x \to c} [f(x) \pm g(x)] = \lim_{x \to c} f(x) \pm \lim_{x \to c} g(x)[/tex]

L'Hopital's Rule

Differentiation

DerivativesDerivative Notation

Derivative Property [Addition/Subtraction]:                                                         [tex]\displaystyle \frac{d}{dx}[f(x) + g(x)] = \frac{d}{dx}[f(x)] + \frac{d}{dx}[g(x)][/tex]

Basic Power Rule:

f(x) = cxⁿf’(x) = c·nxⁿ⁻¹

Step-by-step explanation:

We are given the following limit:

[tex]\displaystyle \lim_{x \to -2} \frac{x^3 + 8}{x^4 - 16}[/tex]

Let's substitute in x = -2 using the limit rule:

[tex]\displaystyle \lim_{x \to -2} \frac{x^3 + 8}{x^4 - 16} = \frac{(-2)^3 + 8}{(-2)^4 - 16}[/tex]

Evaluating this, we arrive at an indeterminate form:

[tex]\displaystyle \lim_{x \to -2} \frac{x^3 + 8}{x^4 - 16} = \frac{0}{0}[/tex]

Since we have an indeterminate form, let's use L'Hopital's Rule. Differentiate both the numerator and denominator respectively:

[tex]\displaystyle \lim_{x \to -2} \frac{x^3 + 8}{x^4 - 16} = \lim_{x \to -2} \frac{3x^2}{4x^3}[/tex]

Substitute in x = -2 using the limit rule:

[tex]\displaystyle \lim_{x \to -2} \frac{3x^2}{4x^3} = \frac{3(-2)^2}{4(-2)^3}[/tex]

Evaluating this, we get:

[tex]\displaystyle \lim_{x \to -2} \frac{3x^2}{4x^3} = \frac{-3}{8}[/tex]

And we have our answer.

Topic: AP Calculus AB/BC (Calculus I/I + II)

Unit:  Limits

wHAT IS THE REFERENCE ANGLE -935°​

Answers

i think it's 35° (^^)

14+6×(9-6)

please answer ​

Answers

Answer:

32

Step-by-step explanation:

14+6(9-6)

[9-6=3]

14+6x3

[6x3=18]

14+18

32

---

hope it helps

Answer:

14+6×(9-6)=32

What are the roots of the polynomial x2 - 4x + 1 ?
Work out your answer on our whiteboard. Then, click the buttons below to
see the step-by-step solution.

Answers

Answer:

x = (2 + √3) , (2 - √3)

Step-by-step explanation:

GIVEN :-

A quadratic polynomial x² - 4x + 1

TO FIND :-

Roots of the quadratic polynomial

GENERAL FORMULAE TO BE USED IN THIS QUESTION :-

Quadratic formulae -

For a polynomial ax² + bx + c , its roots are :-

[tex]x = \frac{-b + \sqrt{b^2 - 4ac} }{2a} \; ; \frac{-b - \sqrt{b^2 - 4ac} }{2a}[/tex]

SOLUTION :-

Use the quadratic formulae to find the roots of the polynomial.

[tex]=> x = \frac{-(-4) + \sqrt{(-4)^2 - 4 \times 1 \times 1c} }{2 \times 1} \; ; \frac{-(-4) - \sqrt{(-4)^2 - 4 \times 1 \times 1} }{2 \times 1}[/tex]

         [tex]= \frac{4 + \sqrt{16 - 4} }{2} \; ; \frac{4- \sqrt{16 - 4}}{2}[/tex]

         [tex]= \frac{4 + \sqrt{12} }{2} \; ; \frac{4- \sqrt{12}}{2}[/tex]

         [tex]= \frac{4 + 2\sqrt{3} }{2} \; ; \frac{4- 2\sqrt{3}}{2}[/tex]

         [tex]= \frac{2(2 + \sqrt{3})}{2} \; ; \frac{2(2- \sqrt{3})}{2}[/tex]

         [tex]= (2 + \sqrt{3} ) \; ; (2 - \sqrt{3} )[/tex]

For a statistics project, Lauren distributed a questionnaire and asked her classmates to fill it out. 2 of them did.

Is this sample of the students in the class likely to be representative? Yes or no

Answers

No, because only a minority of the students answered it.

Cells use the hydrolysis of adenosine triphosphate, abbreviated as ATP, as a source of energy. Symbolically, this reaction can be written asATP(aq)+H2O(l)⟶ADP(aq)+H2PO−4 (aq)where ADP represents adenosine diphosphate. For this reaction, ΔG∘=−30.5kJ/mol.a. Calculate K at 25∘C .b. If all the free energy from the metabolism of glucoseC6H12O6(s)+6O2(g)⟶6CO2(g)+6H2O(l)goes into forming ATP from ADP, how many ATP molecules can be produced for every molecule of glucose?

Answers

Answer:

Step-by-step explanation:

From the given information:

ΔG° = -30.5 kJ/mol

By applying the following equation to calculate the value of K.

ΔG° =-RT㏑K

making ㏑ K  the subject of the formula:

[tex]\mathtt{ In \ K} = \dfrac{\Delta G^0}{-RT}[/tex]

where;

Temperature at 25° C = (25 + 273)K

= 298K

R = 8.3145 J/mol.K (gas cosntant)

[tex]\mathtt{ In \ K} = \dfrac{-30.5 \times 10^{3}\ J /mol} {-(8.3145 \ J/mol. K \times 298 \ K}[/tex]

[tex]\mathtt{ In \ K} = \dfrac{-30.5 \times 10^{3}\ J /mol} {-2477.721 J/mol }[/tex]

㏑K = 12.309

[tex]K = e^{12.309}[/tex]

K = 221682.17

K = 2.22 × 10⁵

b) The reaction for the metabolism of glucose is given as:

[tex]C_6H_{12} O_6 + 6O_{2(g)} \to + 6CO_{2(g)} + 6H_2O_{(l)}[/tex]

From the above expression, let calculate the Gibbs free energy by using the formula:

[tex]\Delta G^0_{rx n }= \Delta G^0_{product}- \Delta G^0_{reactant}[/tex]

[tex]\Delta G^0_{rx n }= [6 \times \Delta G^0_{f}(CO_2) + 6 \times \Delta G^0_{f}(H_2O)] - [1 \times \Delta G^0_{f}(C_6H_{12}O_6) + 6 \times \Delta G^0_{f}(O_2)][/tex]

At standard conditions;

The values of corresponding compounds are substituted into the equation above:

Thus,

[tex]\Delta G^0_{rx n }= [6 \times (-394) + 6 \times (-237)] - [1 \times (-911) + 6 \times (0)] \ kJ/mol[/tex]

[tex]\Delta G^0_{rx n }= [-2364-1422] - [-911+0] \ kJ/mol[/tex]

[tex]\Delta G^0_{rx n }= -3786 +911 \ kJ/mol[/tex]

[tex]\Delta G^0_{rx n }= -2875 \ kJ/mol[/tex]

[tex]\Delta G^0_{rx n }= -2875000 \ J/mol[/tex]

Now, the no of ATP molecules generated = [tex]\dfrac{\Delta G^0 \text{of metabolism for glucose}}{\Delta G^0 \text{of hydrolysis for ATP}}[/tex]

= (-2875000 J/mol ) / -30500 J/mol

= 94.26

≅ 94 ATP molecules generated

Find the value of x in the given figure

Answers

Answer:

20 degrees

Step-by-step explanation:

Angles on a line equal 180 degrees.

180–140=40

40=2x

x=20

20 degrees

Since the whole line should be 180 degrees, and the right number is 140 we Subtract that from 180
180-140=40
2x=40
X=20 Degrees

Some help figuring out the answer?? Also explain a little how you got there

Answers

9514 1404 393

Answer:

  x = 10·cos(θ) -4·cot(θ)

Step-by-step explanation:

Apparently, we are to assume that the horizontal lines are parallel to each other.

The relevant trig relations are ...

  Sin = Opposite/Hypotenuse

  Cos = Adjacent/Hypotenuse

If the junction point in the middle of AB is labeled X, then we have ...

  sin(θ) = 4/BX   ⇒   BX = 4/sin(θ)

  cos(θ) = x/XA   ⇒   XA = x/cos(θ)

Then ...

  BX +XA = AB = 10

Substituting for BX and XA using the above relations, we get

  4/sin(θ) +x/cos(θ) = 10

Solving for x gives ...

  x = (10 -4/sin(θ))·cos(θ)

  x = 10·cos(θ) -4·cot(θ) . . . . . simplify

_____

We used the identity ...

   cot(θ) = cos(θ)/sin(θ)

The sum of 10x + 6 and -x + 8

Answers

9x +14

aisdlkjfhajlsdfhlakjsdhfla

You damage your car and it will cost $7,200 to repair. You have a $1,000 deductible. How much will the insurance company pay?

Answers

Answer:

Amount paid by insurance company = $6,200

Step-by-step explanation:

Given:

Total cost of car damage = $7,200

Amount deductible = $1,000

Find:

Amount paid by insurance company for total damage

Computation:

Amount paid by insurance company = Total cost of car damage - Amount deductible

Amount paid by insurance company = $7,200 - $1,000

Amount paid by insurance company for total damage = $6,200

Create a table to represent the function y=1/3x+4

Answers

X=-3 i am not sure about the answer

Answer:

this is a linear equation. whatever value you set for x, you substitute and make a table that would probably look like this.

      x      |     y

-------------|-----------

5            | 17/3       <------- what would y be if x is 5?

3             | 5                     lets substitute x with 5

               |                          y=1/3*5+4

               |                         y=5/3+4

               |                        y=17/3

Circle the answer choice below that does not equal the following:
– 80/10
1) - 8
2) 80/-10
3) - (80/10)
4) 8

Answers

Answer: 4) 8

Step-by-step explanation:

-80/10=-8

-8 = - 8. - No

80/-10= - 8. - 8=-8 - No

-(80/10)=-(8)=-8. - 8=-8 - No

8 - Yes.

-8 -> I’m sorry if it’s wrong it seems like simple math
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