Can Air Be Compressed Without a Container?

In summary, air is compressible, meaning its volume can be reduced when a force is applied to it. Free air refers to air that is not confined or compressed, which is the air we breathe in our daily lives. When air is compressed, its density and pressure increase while its volume decreases, leading to an increase in temperature. However, air cannot be compressed to an infinite extent and at a certain point, it becomes a liquid. Knowing the compressibility of air is important in various fields, including aerodynamics, meteorology, and engineering, as it helps us design and test devices, predict weather patterns, and study gas behavior in different environments.
  • #1
Becourbin
1
0
I have read in different theorem's (Bernoulli's for example), that free air is considered incompressible below a speed of 0.4 Mach.
If I were to place air in a jug and reuce the amount of space it occupies, then I am compressing it, but is this possible under certain conditions in free air?
 
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  • #2
That's a generalization about how air reacts to solid objects moving through the air. Somewhere between mach .3 and mach .4, there's about 5% compression in most common situations. It's less at lower speeds, enough that simplified mathematical models can ignore it.
 

1. Is air compressible?

Yes, air is compressible. This means that its volume can be reduced when a force is applied to it.

2. What is free air?

Free air refers to air that is not confined or compressed. It is the air that we breathe in our everyday lives.

3. How does compression affect the properties of air?

When air is compressed, its density and pressure increase, while its volume decreases. This leads to an increase in temperature, as stated by the ideal gas law.

4. Can air be compressed to an infinite extent?

No, air cannot be compressed to an infinite extent. At a certain point, known as the critical point, the properties of air change and it becomes a liquid.

5. Why do we need to know if free air is compressible?

Understanding the compressibility of air is important in many fields, such as aerodynamics, meteorology, and engineering. It helps us design and test various devices, predict weather patterns, and study the behavior of gases in different environments.

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