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No straw on Earth works beyond ten metres in length.

When you suck, you create no pull, only low pressure: the air pressure outside pushes the drink upward. That pressure supports at most about ten metres of water, one bar. Even with a perfect vacuum in your mouth, water would stall below that. So no suction pump lifts water from deeper than ten metres; deeper wells need pumps down in the shaft.

Useful: A well deeper than ten metres needs a submersible pump, not one at the surface.

Source: de.wikipedia.org

AlltagLuftdruckPhysik

Difficulty:

Question on this card

What pushes the drink up the straw?

  1. The suction force of your lungs
  2. Air pressure on the liquid in the glass
  3. Surface tension
  4. Capillary action of the straw
Show the answer

Correct: Air pressure on the liquid in the glass

You only lower the pressure inside the straw. Outside air pressure does the pushing, and it is good for about ten metres of water.

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