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How easy is it to breathe through a straw? when you breathe deeply, you pull in 4.0 l of air in about 3.0 s . this requires a pressure difference of about 4.0 kpa between the air in your lungs and the outside air. what additional pressure difference is required to pull 20 ∘c air through a straw that is 22 cm long and 0.56 cm in diameter?

User Rednaks
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Final answer:

The ease of breathing through a straw depends on the additional pressure difference required to draw air through the straw's dimensions, which can be estimated using the Hagen-Poiseuille equation, but precise calculations cannot be completed without data on air viscosity.

Step-by-step explanation:

To determine how easy it is to breath through a straw, we must calculate the additional pressure difference required to pull 20°C air through a straw of given dimensions. The question involves applying principles of fluid dynamics and pressure.

Using the Hagen-Poiseuille equation, which is expressed as Q = (πΔPr^4) / (8ηl), where Q is the volume flow rate, ΔP is the pressure difference, r is the radius of the straw, η is the viscosity of the fluid (in this case, air), and l is the length of the straw, we can find the additional pressure needed. However, complete calculations would require knowledge of the viscosity of air at 20°C, and the provided information does not include the viscosity or suggest that the straw is at its limit of creating a vacuum to elevate water. Therefore, a precise answer cannot be given without additional data.

It is important to note that as a person sucks the air out of a straw, it creates a low pressure zone inside, and the atmospheric pressure outside then pushes the fluid up the straw into the person's mouth. The height to which a liquid can be elevated via a straw is ultimately limited by atmospheric pressure.

User KarelZe
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