1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
nydimaria [60]
3 years ago
11

If you measured a pressure difference of 50 mm of mercury across a pitot tube placed in a wind tunnel with 200 mm diameter, what

is the velocity of air in the wind tunnel? What is the Reynolds number of the air flowing in the wind tunnel? Is the flow laminar or turbulent? Assume air temperature is 25°C.
Engineering
1 answer:
mart [117]3 years ago
4 0

Answer:

V=33.66 m/s

Re=448.8\times 10^6

Re>4000, The flow is turbulent flow.

Explanation:

Given that

Pressure difference  = 50 mm of Hg

We know that density of Hg=136000Kg/m^3

ΔP= 13.6 x 1000 x 0.05 Pa

ΔP=680 Pa

Diameter of tunnel = 200 mm

Property of air at 25°C

ρ=1.2Kg/m^3

Dynamic viscosity

\mu =1.8\times 10^{-8}\ Pa.s

Velocity of fluid given as

V=\sqrt{\dfrac{2\Delta P}{\rho_{air}}}

V=\sqrt{\dfrac{2\times 680}{1.2}}

V=33.66 m/s

Reynolds number

Re=\dfrac{\rho _{air}Vd}{\mu }

Re=\dfrac{1.2\times 33.66\times 0.2}{1.8\times 10^{-8}}

Re=448.8\times 10^6

Re>4000,So the flow is turbulent flow.

You might be interested in
A rigid, sealed tank initially contains 2000 kg of water at 30 °C and atmospheric pressure. Determine: a) the volume of the tank
Bad White [126]

Given:

mass of water, m = 2000 kg

temperature, T = 30^{\circ}C = 303 K

extacted mass of water = 100 kg

Atmospheric pressure, P = 101.325 kPa

Solution:

a) Using Ideal gas equation:

PV = m\bar{R}T                                        (1)

where,

V = volume

m = mass of water

P = atmospheric pressure

\bar{R} = \frac{R}{M}

R= Rydberg's constant = 8.314 KJ/K

M = molar mass of water = 18 g/ mol

Now, using eqn (1):

V = \frac{m\bar{R}T}{P}

V = \frac{2000\times \frac{8.314}{18}\times 303}{101.325}

V = 2762.44 m^{3}

Therefore, the volume of the tank is V = 2762.44 m^{3}

b) After extracting 100 kg of water, amount of water left, m' = m - 100

m' = 2000 - 100 = 1900 kg

The remaining water reaches thermal equilibrium with surrounding temperature at T' = 30^{\circ}C = 303 K

At equilibrium, volume remain same

So,

P'V = m'\bar{R}T'

P' = \frac{1900\times \frac{8.314}{18}\times 303}{2762.44}      

Therefore, the final pressure is P' = 96.258 kPa

4 0
3 years ago
Imagine the arc of a football as it flies through the air. How does this motion illustrate classical mechanics?
BigorU [14]

Answer: Maybe A

Explanation:

7 0
1 year ago
Read 2 more answers
java Write a program that simulates tossing a coin. Prompt the user for how many times to toss the coin. Code a method with no p
max2010maxim [7]

Answer:

The solution code is written in Java.

  1. public class Main {
  2.    public static void main(String[] args) {
  3.        Scanner inNum = new Scanner(System.in);
  4.        System.out.print("Enter number of toss: ");
  5.        int num = inNum.nextInt();
  6.        for(int i=0; i < num; i++){
  7.            System.out.println(toss());
  8.        }
  9.    }
  10.    public static String toss(){
  11.        String option[] = {"heads", "tails"};
  12.        Random rand = new Random();
  13.        return option[rand.nextInt(2)];
  14.    }
  15. }

Explanation:

Firstly, we create a function <em>toss()</em> with no parameter but will return a string (Line 14). Within the function body, create an option array with two elements, "heads" and "tails" (Line 15). Next create a Random object (Line 16) and use <em>nextInt()</em> method to get random value either 0 or 1. Please note we need to pass the value of 2 into <em>nextInx() </em>method to ensure the random value generated is either 0 or 1.  We use this generate random value as an index of <em>option </em>array and return either "heads" or "tails" as output (Line 17).

In the main program, we create Scanner object and use it to prompt user to input an number for how many times to toss the coin (Line 6 - 7). Next, we use the input num to control how many times a for loop should run (Line 9). In each round of the loop, call the function <em>toss() </em>and print the output to terminal (Line 10).  

4 0
3 years ago
Read 2 more answers
PythonA group of statisticians at a local college has asked you to create a set of functionsthat compute the median and mode of
skelet666 [1.2K]

Answer:

  1. def median(l):
  2.    if(len(l) == 0):
  3.       return 0
  4.    else:
  5.        l.sort()
  6.        if(len(l)%2 == 0):
  7.            index = int(len(l)/2)
  8.            mid = (l[index-1] + l[index]) / 2
  9.        else:
  10.            mid = l[len(l)//2]  
  11.        return mid  
  12. def mode(l):
  13.    if(len(l)==0):
  14.        return 0
  15.    mode = max(set(l), key=l.count)
  16.    return mode  
  17. def mean(l):
  18.    if(len(l)==0):
  19.        return 0
  20.    sum = 0
  21.    for x in l:
  22.        sum += x
  23.    mean = sum / len(l)
  24.    return mean
  25. lst = [5, 7, 10, 11, 12, 12, 13, 15, 25, 30, 45, 61]
  26. print(mean(lst))
  27. print(median(lst))
  28. print(mode(lst))

Explanation:

Firstly, we create a median function (Line 1). This function will check if the the length of list is zero and also if it is an even number. If the length is zero (empty list), it return zero (Line 2-3). If it is an even number, it will calculate the median by summing up two middle index values and divide them by two (Line 6-8). Or if the length is an odd, it will simply take the middle index value and return it as output (Line 9-10).

In mode function, after checking the length of list, we use the max function to estimate the maximum count of the item in list (Line 17) and use it as mode.

In mean function,  after checking the length of list,  we create a sum variable and then use a loop to add the item of list to sum (Line 23-25). After the loop, divide sum by the length of list to get the mean (Line 26).

In the main program, we test the three functions using a sample list and we shall get

20.5

12.5

12

3 0
3 years ago
Water is flowing into the top of an open cylindrical tank (which has a diameter D) at a volume flow rate of Qi and the water flo
deff fn [24]

Answer:

Z = 3 + 0.23t

The water level is rising

Explanation:

Please see attachment for the equation

8 0
3 years ago
Read 2 more answers
Other questions:
  • Which conditions are required for nuclear fusion to begin
    8·1 answer
  • For a steel alloy it has been determined that a carburizing heat treatment of 7 hour duration will raise the carbon concentratio
    12·1 answer
  • A decorative fountain was built so that water will rise to a hieght of 8 feet above the exit of the pipe. the pipe is 3/4 diamet
    5·1 answer
  • An intranet is a restricted network that relies on Internet technologies to provide an Internet-like environment within the comp
    11·1 answer
  • There are 22 gloves in a drawer: 5 pairs of red gloves, 4 pairs of yellow, and 2 pairs of green. You select the gloves in the da
    13·1 answer
  • Why would Chris most likely conclude that he should seek help? A. He feels in control of his emotions even though people annoy h
    15·2 answers
  • What is the purpose of making a jello pool
    6·1 answer
  • What is the moment that the wrench puts on the bolt?
    13·1 answer
  • An ideal gas is contained in a closed assembly with an initial pressure and temperature of
    14·1 answer
  • Write down about the water source selection criteria​
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!