Struggling with a Homework Problem - Need Assistance

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SUMMARY

The discussion centers on calculating the maximum height of a vertical soda straw that can be used to drink, focusing on the principles of fluid mechanics. The key equation mentioned is p = ρgh, where ρ represents the density of the fluid, g is the acceleration due to gravity, and h is the height of the fluid column. The pressure at the top of the straw must not exceed atmospheric pressure (101.3 kPa) for the straw to function properly. Increasing ambient pressure above 1 atm can allow for a greater height of the straw.

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Gott_ist_tot
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I received a homework problem that I need guidance on where to start.

What is the longest vertical soda straw you could possibly drink from?

I do not know where to start on this problem. A small push in the right direction would be greatly appreciated.
 
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As I posted this I had a possible epiphany.

p = [tex]/rho[/tex]gd

If the depth at which the straw is submerged makes rho*g*d greater than 101.3 kPa than the water above the end of the straw keeps the water down. Although now I know that won't work because that is how deep the straw is not how long it is.
 
Gott_ist_tot said:
As I posted this I had a possible epiphany.

p = [tex]/rho[/tex]gd

If the depth at which the straw is submerged makes rho*g*d greater than 101.3 kPa than the water above the end of the straw keeps the water down. Although now I know that won't work because that is how deep the straw is not how long it is.
in TeX, write /rho as \rho to get the correct letter.

Your approach is correct. One must identify the height (depth) of water, which gives a pressure drop of 1 atm, since it is assumed that the reservoir of water is at one atmosphere (101325 Pa) absolute, and the lowest pressure one could achieve is a pure vacuum of ~ 0 Pa.

The only way to obtain a greater head of water is to increase the ambient pressure above 1 atm.
 

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