What is the tallest straw that you could, in principle, drink from

  • Thread starter Thread starter ruffkilla
  • Start date Start date
  • Tags Tags
    Principle
Click For Summary
SUMMARY

The maximum height of a straw from which one can drink water is determined to be 10 meters, based on the approximation of gravitational acceleration at 10 m/s². The fundamental principle involves atmospheric pressure pushing the water up the straw, which can be calculated using the equation P1 + ρgh1 = P2 + ρgh2. In this scenario, P1 is 0 Pa and h1 is 0, leading to the conclusion that P2 equals atmospheric pressure, which supports a height of 10 meters for water.

PREREQUISITES
  • Understanding of fluid mechanics principles
  • Basic knowledge of atmospheric pressure and its effects
  • Familiarity with the concept of vacuum and pressure differentials
  • Ability to apply the hydrostatic pressure formula (P = ρgh)
NEXT STEPS
  • Research the effects of atmospheric pressure on fluid dynamics
  • Explore the principles of hydrostatics in greater detail
  • Study the relationship between pressure and height in different fluids
  • Learn about practical applications of suction and vacuum in engineering
USEFUL FOR

Students of physics, engineers, and anyone interested in fluid mechanics and the principles of pressure and suction.

ruffkilla
Messages
9
Reaction score
0
As a stunt, you want to sip some water through a very long, vertical straw. what is the tallest straw that you could, in principle, drink from in this way?
 
Physics news on Phys.org
Well, what do you think?
 
well i know the answer is 10 m if you round gravity to 10 m/s^2. i also know that the pressure on the top of the straw is 0 Pa. but besides that i have no clue, that's why I am asking it.
 
When you sip through a straw, what pushes the water up the straw?
 
the vacuum created by sucking your cheeks in.
i came up with this solution.
P1 + rough (g) (h1) = P2 + rough (g) (h2)
P1=0, h1=0
so P2 = rough (g)(h2)
1 atm= 1000(10)(h2)
1.01 EE5=1.0EE4(h2)
h2= 10 m

but I am not sure.
 
Looks like you've got it. It's atmospheric pressure that pushes the water up the straw. The maximum height of water that can be supported by the air will be found by setting the water pressure (\rho g h) equal to atmospheric pressure.
 

Similar threads

Replies
2
Views
2K
Replies
7
Views
2K
  • · Replies 11 ·
Replies
11
Views
10K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 9 ·
Replies
9
Views
3K
  • · Replies 12 ·
Replies
12
Views
5K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 5 ·
Replies
5
Views
30K
  • · Replies 22 ·
Replies
22
Views
8K
  • · Replies 8 ·
Replies
8
Views
2K