Pre Test

Water flows through a pipe of 100 mm at the rate of 0.9 m3 per minute at section A. It tapers to 50mm diameter at B, A being 1.5

pochemuha

Answer:

The velocities in points A and B are 1.9 and 7.63 m/s respectively. The Pressure at point B is 28 Kpa.

Explanation:

Assuming the fluid to be incompressible we can apply for the continuity equation for fluids:

$Aa.Va=Ab.Vb=Q$

Where A, V and Q are the areas, velocities and volume rate respectively. For section A and B the areas are:

$Aa=\frac{pi.Da^2}{4}= \frac{\pi.(0.1m)^2}{4}=7.85*10^{-3}\ m^3$

$Ab=\frac{pi.Db^2}{4}= \frac{\pi.(0.05m)^2}{4}=1.95*10^{-3}\ m^3$

Using the volume rate:

$Va=\frac{Q}{Aa}=\frac{0.9m^3}{7.85*10^{-3}\ m^3} = 1.9\ m/s$

$Vb = \frac{Q}{Ab}= \frac{0.9m^3}{1.96*10^{-3}\ m^3} = 7.63\ m/s$

Assuming no losses, the energy equation for fluids can be written as:

$Pa+\frac{1}{2}pa.Va^2+pa.g.za=Pb+\frac{1}{2}pb.Vb^2+pb.g.zb$

Here P, V, p, z and g represent the pressure, velocities, height and gravity acceleration. Considering the zero height level at point A and solving for Pb:

$Pb=Pa+\frac{1}{2}pa(Va^2-Vb^2)-pa.g.za$

Knowing the manometric pressure in point A of 70kPa, the height at point B of 1.5 meters, the density of water of 1000 kg/m^3 and the velocities calculated, the pressure at B results:

$Pb = 70000Pa+ \frac{1}{2}*1000\ \frac{kg}{m^3}*((1.9m/s)^2 - (7.63m/s)^2) - 1000\frac{kg}{m^3}*9,81\frac{m}{s^2}*1.5m$

$Pb = 70000\ Pa-27303\ Pa - 14715\ Pa$

$Pb = 27,996\ Pa = 28\ kPa$

6 0

3 years ago

Do not use C++ pointers (this is not a topic of this course).

noname [10]

The program is an illustration of functions in C++

C++ functions are collection of named program statements that are executed when called

<h3>The C++ program</h3>

The program in C++, where comments are used to explain each action is as follows:

#include <iostream>

#include <cmath>

using namespace std;

//This defines the boolean method

bool isoscelesTriangleHeightAndArea(double base, double hypotenuse, double height, double area) {

//This checks for invalid base and height

if(base < 0 || hypotenuse < 0){

return false;

}

//This returns true if base and height are valid

return true;

}

//The main begins here

int main(){

//This initializes the variables

double base, hypotenuse, height, area;

//This gets input for base and hypotenuse

cout<<"Base: "; cin>>base;

cout<<"Hypotenuse: "; cin>>hypotenuse;

//The calls the boolean method

bool success = isoscelesTriangleHeightAndArea(base, hypotenuse, height, area);

//If success is True

while (success){

//This calculates height

height = sqrt(hypotenuse*hypotenuse - (base/2) * (base/2));

//This calculates area

area = 0.5 * base * height;

//This prints height

cout << "Triangle height is " << height << endl;

//This prints area

cout << "Triangle area is " << area << endl;

//This gets input for base and hypotenuse

cout<<"Base: "; cin>>base;

cout<<"Hypotenuse: "; cin>>hypotenuse;

bool success = isoscelesTriangleHeightAndArea(base, hypotenuse, height, area);

}

cout << "Invalid Input!" << endl;

}

Read more about C++ programs at:

brainly.com/question/24833629

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4 0

2 years ago

Question 1 : Replacement [42 Pts] Consider the following page reference string:

MakcuM [25]

Answer:

Optimal

Time 123456789101112

RS. ecbeagdcegda

F0. eeeeeeeee e e a

F1 c c c c c c c c c c c

F2 b b b g g g g g g g

F3 a a d d d d d d

Page fault? * * * * * * *

Total page fault:7

2. LRU

Time 1 2 3 4 5 6 7 8 9 10 11 12

RS e c b e a g d c e g d a

F0 e e e e e e e c c c c a

F1 c c c c g g g g g g g

F2 b b b b d d d d d d

F3 a a a a e e e e

Page fault? Y Y Y N Y Y Y Y Y N N Y Total page fault:9

3. LRU approximation algorithm: Second chance

Time 1 2 3 4 5 6 7 8 9 10 11 12

RS e c b e a g d c e g d a

F0 0,e 0,e 0,e 1,e 1,e 0,e 0,e 0,e 1,e 1,e 1,e 0,e

F1 0,c 0,c 0,c 0,c 0,g 0,g 0,g 0,g 1,g 1,g 0,g

F20,b0,b0,b0,b0,d0,d0,d0,d1,d0,dF30,a0,a0,a0,c0,c0,c0,c0,a

Page fault? YYYNYYYYNNNY

Total page fault: 8

4 0

3 years ago

Read 2 more answers

Which one of these is NOT considered a skill?

Ugo [173]

Answer:

number 2 people skills

Explanation:

i think people skills does not make cense because you can not control what people think

4 0

3 years ago

Read 2 more answers

the left rear brake drum is scored, but the right rear drum looks as good as new. technician a says the left-side drum should be

Romashka-Z-Leto [24]

Technician b is correct because the left rear brake drum is scored, but the right rear drum looks as good as new then both sides should be remachined to a similar diameter.

A brake drum is a revolving cylinder-shaped component that is friction-activated by a set of shoes or pads pressing outward against it. Drum brakes are brakes where shoes are pressed against the inner surface of the drum. Drum brakes are frequently used at the rear. Compared to disc brakes, these brakes have more parts and are more difficult to maintain, but they cost less to make and are simple to add an emergency braking mechanism. The front and rear brakes are standard equipment on all automobiles. Your car may have a "disc brake" system on all four wheels, a "drum brake" system on all four wheels, or a combination of the two. Typically, the front brakes of your car have a disc system, and the rear brakes have a drum system.

Learn more about brake drum here:

brainly.com/question/14937026

#SPJ4

7 0

1 year ago