?Why the efficiency of Class A amplifier is very poor

A 14 inch diameter pipe is decreased in diameter by 2 inches through a contraction. The pressure entering the contraction is 28

Delicious77 [7]

Answer:

5984.67N

Explanation:

A 14 inch diameter pipe is decreased in diameter by 2 inches through a contraction. The pressure entering the contraction is 28 psi and a pressure drop of 2 psi occurs through the contraction if the upstream velocity is 4.0 ft/sec. What is the magnitude of the resultant force (lbs) needed to hold the pipe in place?

from continuity equation

v1A1=v2A2

equation of continuity

v1=4ft /s=1.21m/s

d1=14 inch=.35m

d2=14-2=0.304m

A1=pi*d^2/4

0.096m^2

a2=0.0706m^2

from continuity once again

1.21*0.096=v2(0.07)

v2=1.65

force on the pipe

(p1A1- p2A2) + m(v2 – v1)

from bernoulli

p1 + ρv1^2/2 = p2 + ρv2^2/2

difference in pressure or pressure drop

p1-p2=2psi

13.789N/m^2=rho(1.65^2-1.21^2)/2

rho=21.91kg/m^3

since the pipe is cylindrical

pressure is egh

13.789=21.91*9.81*h

length of the pipe is

0.064m

AH=volume of the pipe(area *h)

the mass =rho*A*H

0.064*0.07*21.91

m=0.098kg

(193053*0.096- 179263.6* 0.07) + 0.098(1.65 – 1.21)

force =5984.67N

4 0

3 years ago

LAB 3.3 – Working with String Input and Type CastingStep 1: RemovefindErrors.cppfrom the project and add thepercentage.cppprogra

jolli1 [7]

Answer:

// Program is written in C++ Programming Language

// Comments are used for explanatory purpose

#include<iostream>

using namespace std;

int main ()

{

// Variable declaration

string name;

int numQuestions;

int numCorrect;

double percentage;

//Prompt to enter student's first and last name

cout<<"Enter student's first and last name";

cin>>name; // this line accepts input for variable name

cout<<"Number of question on test"; //Prompt to enter number of questions on test

cin>> numQuestions; //This line accepts Input for Variable numQuestions

cout<<"Number of answers student got correct: "; // Prompt to enter number of correct answers

cin>>numCorrect; //Enter number of correct answers

percentage = numCorrect * 100 / numQuestions; // calculate percentage

cout<<name<<" "<<percentage<<"%"; // print

return 0;

}

Explanation:

The code above calculates the percentage of a student's score in a certain test.

The code is extracted from the Question and completed after extraction.

It's written in C++ programming language

4 0

3 years ago

How would I get this python code to run correctly? it's not working.

Elanso [62]

Answer:

See Explanation

Explanation:

This question requires more information because you didn't state what the program is expected to do.

Reading through the program, I can assume that you want to first print all movie titles then prompt the user for a number and then print the move title in that location.

So, the correction is as follows:

Rewrite the first line of the program i.e. movie_titles = ["The grinch......."]

for each_movie_titles in movie_titles:

print(each_movie_titles)

usernum = int(input("Number between 0 and 9 [inclusive]: "))

if usernum<10 and usernum>=0:

print(movie_titles[usernum])

Line by line explanation

This iterates through the movie_titles list

for each_movie_titles in movie_titles:

This prints each movie title

print(each_movie_titles)

This prompts the user for a number between 0 and 9

usernum = int(input("Number between 0 and 9 [inclusive]: "))

This checks for valid range

if usernum<10 and usernum>=0:

If number is valid, this prints the movie title in that location

print(movie_titles[usernum])

6 0

3 years ago

The proposed grading at a project site will consist of 25,100 m3 of cut and 23,300 m3 of fill and will be a balanced earthwork j

Anna [14]

Answer:

the volume of water that will be required to bring these soils to the optimum moisture content is 1859 kL

Explanation:

Given that;

volume of cut = 25,100 m³

Volume of dry soil fill = 23,300 m³

Weight of the soil will be;

⇒ 93% × 18.3 kN/m³ × 23,300 m³

= 0.93 × 426390 kN 3

= 396,542.7 kN

Optimum moisture content = 12.9 %

Required amount of moisture = (12.9 - 8.3)% = 4.6 %

So,

Weight of water required = 4.6% × 396,542.7 = 18241 kN

Volume of water required = 18241 / 9.81 = 1859 m³

Volume of water required = 1859 kL

Therefore, the volume of water that will be required to bring these soils to the optimum moisture content is 1859 kL

6 0

3 years ago

A two-dimensional flow field described by

Oduvanchick [21]

Answer:

the answer is

Explanation:

<h2> We now focus on purely two-dimensional flows, in which the velocity takes the form </h2><h2>u(x, y, t) = u(x, y, t)i + v(x, y, t)j. (2.1) </h2><h2>With the velocity given by (2.1), the vorticity takes the form </h2><h2>ω = ∇ × u = </h2><h2> </h2><h2>∂v </h2><h2>∂x − </h2><h2>∂u </h2><h2>∂y </h2><h2>k. (2.2) </h2><h2>We assume throughout that the flow is irrotational, i.e. that ∇ × u ≡ 0 and hence </h2><h2>∂v </h2><h2>∂x − </h2><h2>∂u </h2><h2>∂y = 0. (2.3) </h2><h2>We have already shown in Section 1 that this condition implies the existence of a velocity </h2><h2>potential φ such that u ≡ ∇φ, that is </h2><h2>u = </h2><h2>∂φ </h2><h2>∂x, v = </h2><h2>∂φ </h2><h2>∂y . (2.4) </h2><h2>We also recall the definition of φ as </h2><h2>φ(x, y, t) = φ0(t) + Z x </h2><h2>0 </h2><h2>u · dx = φ0(t) + Z x </h2><h2>0 </h2><h2>(u dx + v dy), (2.5) </h2><h2>where the scalar function φ0(t) is arbitrary, and the value of φ(x, y, t) is independent </h2><h2>of the integration path chosen to join the origin 0 to the point x = (x, y). This fact is </h2><h2>even easier to establish when we restrict our attention to two dimensions. If we consider </h2><h2>two alternative paths, whose union forms a simple closed contour C in the (x, y)-plane, </h2><h2>Green’s Theorem implies that </h2><h2> </h2><h2> </h2><h2> </h2><h2> </h2><h2> </h2><h2></h2><h2></h2>

5 0

3 years ago

?Why the efficiency of Class A amplifier is very poor​

?Why the efficiency of Class A amplifier is very poor