Solve Air Pressure Problem: Find y(x) Given y'(x)

In summary, the problem asks to find the air pressure at 10973 m altitude, given that the rate of change of pressure is proportional to the pressure itself. At 5486 m, the pressure has decreased to half of its value at mean sea level. The given information implies that the derivative of pressure with respect to altitude is proportional to the pressure itself, with a constant of proportionality.
  • #1
zetshield21
6
0
Problem:
the efficiency of turbofan engines of commercial airplanes depend on air pressure and usually is maximum near about 10973 m, above mean sea level. Find the air pressure y(x) at this height given the rate of change y'(x) is proportional to the pressure, and at 5486 m the pressure has decrease to half its value y0 at mean sea level.

note: please solve my problem please!
 
Physics news on Phys.org
  • #2
Only you can solve this problem. If you show some work, you might get some comments about whether it is correct.
 
  • #3
zetshield21 said:
Problem:
the efficiency of turbofan engines of commercial airplanes depend on air pressure and usually is maximum near about 10973 m, above mean sea level. Find the air pressure y(x) at this height given the rate of change y'(x) is proportional to the pressure, and at 5486 m the pressure has decrease to half its value y0 at mean sea level.

note: please solve my problem please!

The words in bold imply that

dp/dz = kp, where k is a constant, p is the pressure, and z is the altitude
 
  • #4
This thread is closed. zetshield21 -- check your PMs. You may only repost if you follow the Homework Help Template and rules.

And guys, when you see somebody post like this with zero effort shown, please click the Report button on the OP's post to have a Mentor deal with it. Thanks.
 
  • #5


I would approach this problem by first understanding the relationship between air pressure and altitude. Air pressure decreases as altitude increases, with a known rate of change.

Using the information provided, we know that at 5486 m, the pressure has decreased to half its value at sea level. This means that at 5486 m, the pressure is equal to y0/2. We can use this information to set up an equation:

y(x) = y0/2

Next, we are given that the rate of change of pressure, y'(x), is proportional to the pressure itself. This can be written as:

y'(x) ∝ y(x)

We can rewrite this using a constant of proportionality, k:

y'(x) = k * y(x)

Now, we can substitute our equation for y(x) into this equation:

y'(x) = k * (y0/2)

We are also given that at 10973 m, the efficiency of the turbofan engines is maximum. This means that at this altitude, the pressure is at its maximum value, which we can represent as ymax. We can use this information to set up another equation:

y(10973) = ymax

Now we have two equations with two unknowns (k and ymax). We can solve for k by plugging in the values we know:

k = y'(10973) / (y0/2)

Next, we can use this value of k to solve for ymax:

ymax = y(10973) = k * (y0/2)

Finally, we can substitute this value of ymax into our original equation for y(x):

y(x) = (y0/2) * (y(10973)/y0)

This gives us the air pressure at any altitude x, given the known rate of change y'(x) and the pressure at sea level, y0.

In conclusion, the air pressure at an altitude of 10973 m is equal to (y0/2) * (y(10973)/y0), where y(10973) is the maximum pressure at this altitude and y0 is the pressure at sea level. This solution takes into account the given information about the rate of change of pressure and the maximum efficiency of the turbofan engines at a specific altitude.
 

1. What is air pressure and why is it important to solve problems involving it?

Air pressure is the force exerted by the weight of air molecules in a specific area. It is important to solve problems involving air pressure because it affects many natural and man-made phenomena, such as weather patterns, fluid flow, and the performance of various machines and equipment.

2. What is the difference between absolute and gauge pressure?

Absolute pressure is the total pressure exerted by the weight of air molecules and any other external force, while gauge pressure is the difference between absolute pressure and the atmospheric pressure. Gauge pressure is often used in practical applications, while absolute pressure is used in scientific calculations.

3. How is air pressure measured and what are the units of measurement?

Air pressure is measured using a device called a barometer, which typically uses a column of mercury or aneroid capsules to indicate the pressure. The units of measurement for air pressure are pascals (Pa) in the SI system, or pounds per square inch (psi) in the imperial system. Other common units include atmospheres (atm) and millibars (mb).

4. What is the ideal gas law and how is it related to air pressure problems?

The ideal gas law, also known as the universal gas law, states that the pressure, volume, and temperature of an ideal gas are related by the equation PV = nRT, where P is pressure, V is volume, n is the number of moles of gas, R is the gas constant, and T is temperature. This law is often used in air pressure problems, as it describes the behavior of gases in various conditions.

5. How can I solve problems involving air pressure using calculus?

To solve air pressure problems using calculus, you will need to use the first derivative (y') to find the rate of change of air pressure at a specific point, and then integrate the first derivative to find the original function (y). This will give you the equation y(x) that represents the air pressure at any given point x. Additionally, you may need to use the chain rule or other calculus techniques to solve more complex problems involving air pressure.

Similar threads

  • Engineering and Comp Sci Homework Help
Replies
6
Views
1K
  • Engineering and Comp Sci Homework Help
Replies
1
Views
1K
Replies
2
Views
4K
  • Engineering and Comp Sci Homework Help
Replies
13
Views
3K
  • Engineering and Comp Sci Homework Help
Replies
11
Views
6K
  • Engineering and Comp Sci Homework Help
Replies
2
Views
18K
  • DIY Projects
2
Replies
36
Views
8K
Replies
13
Views
20K
Replies
5
Views
2K
  • Engineering and Comp Sci Homework Help
Replies
6
Views
7K
Back
Top