Pressure needed inside an Air Mattress to deflate in given time

In summary, the conversation discusses the task of determining the necessary pressure inside an air mattress in order to completely deflate it in 2 seconds by applying pressure and using a small hole for air to escape. The ideal gas law and Bernoulli's equation were considered but did not seem to be applicable. The correct volume of the air mattress is 4.4 m^3, not 44 m^3 as originally stated. The conversation also mentions the possibility of using an equation for gases similar to Bernoulli's equation.
  • #1
hunnedlicks
4
0

Homework Statement


I am trying to figure out what pressure I need inside an air mattress if I want it to deflate in a given time and given also that I'm applying pressure on it. Basically, I have an air mattress with a small hole in it for air to come out of, and I need to figure out how much pressure I need inside of it if I want to completely deflate it in, let's say, 2 seconds by dropping a weight on it (which will apply some pressure on the mattress). The mattress doesn't not stretch (is not elastic); it's volume is 4.4 m^3. The time I want the mattress to deflate in is about 2 seconds. The Pressure I will be applying on the mattress over those two seconds is about 28000 Pa. I will be filling the mattress with air. The hole has a diameter of 2cm.

Homework Equations


ideal gas law? bernoulli's equation? poiseulle's equation?

The Attempt at a Solution


I tried looking at a version of bernoulli's equation that is supposed to work for compressible fluids, (and therefore gases?), but I don't think it will apply. The ideal gas law doesn't seem to take time into account, so I don't think it will work, at least not by itself. I was hoping there would be an equation like bernoulli's equation or similar fluid dynamic equations but for gases.
I can't seem to find an equation that might be useful, so I don't even know where to start.

Thanks in advance!
 
Last edited:
Physics news on Phys.org
  • #2
I can't imagine what you describe is possible. Also i think you may have the volume of your air mattress a bit off. 44 cubic meters is HUGE! If you wanted all that air through a 2cm hole in 2 seconds then it would have to go super sonic!

You are looking for a pressure drop across an orifice and then estimating a flow rate...
 
  • #3
Woops! You're right, I messed up, I meant to type 4.4 meters cubed, not 44. Thanks for the reply!
 

1. What is the necessary pressure needed inside an air mattress to deflate in a given time?

The necessary pressure needed inside an air mattress to deflate in a given time will vary depending on the size and material of the mattress. However, a general rule of thumb is that the pressure should be around 0.5-1 psi (pounds per square inch) for a standard twin-sized air mattress to fully deflate in 5-10 minutes.

2. How do you measure the pressure inside an air mattress?

The pressure inside an air mattress can be measured using a pressure gauge or a manometer. These tools measure the amount of force exerted by the air molecules inside the mattress, which is then converted into psi or other units of measurement.

3. Can the pressure inside an air mattress be adjusted to control the deflation time?

Yes, the pressure inside an air mattress can be adjusted to control the deflation time. By adjusting the amount of air inside the mattress, you can increase or decrease the pressure, which will affect the rate of deflation. However, it is important to keep in mind that excessively high or low pressure can damage the mattress and affect its overall performance.

4. What factors can affect the pressure needed inside an air mattress to deflate?

There are several factors that can affect the pressure needed inside an air mattress to deflate, such as the size and material of the mattress, the temperature and humidity of the surrounding environment, and the weight and movement of the person(s) using the mattress. These factors can impact the elasticity and air retention of the mattress, which can affect the necessary pressure for deflation.

5. Is there a specific formula to determine the pressure needed inside an air mattress for a desired deflation time?

There is no specific formula to determine the pressure needed inside an air mattress for a desired deflation time. The ideal pressure will depend on the factors mentioned above and may require some experimentation. It is important to follow the manufacturer's recommendations and guidelines for inflating and deflating the air mattress to ensure optimal performance and longevity.

Similar threads

Adiabatic Expansion of Pressurized Air in a Piston-Cylinder Setup
    • Introductory Physics Homework Help
Replies
8
Views
743
Density of air at one atmosphere pressure
    • Introductory Physics Homework Help
Replies
3
Views
998
Mercury barometer with a small amount of air
    • Introductory Physics Homework Help
Replies
7
Views
1K
Thermal physics problem -- Pressure and temperature of air in a refrigerator
    • Introductory Physics Homework Help
Replies
2
Views
4K
Pressure distribution on an air mattress
    • Mechanics
Replies
1
Views
1K
Trouble solving for end state of two control volumes in a rigid tank
    • Introductory Physics Homework Help
Replies
12
Views
847
Air mattress pressure question regarding partial inflation
    • Mechanics
Replies
2
Views
1K
Mixing two ideal gases with different V, T at constant pressure
    • Introductory Physics Homework Help
Replies
16
Views
2K
Time taken by a balloon to deflate
    • Introductory Physics Homework Help
Replies
17
Views
3K
What determines the pressure inside this experimental setup?
    • Materials and Chemical Engineering
Replies
2
Views
279

Hot Threads

Recent Insights

Back
Top