Today, I drank a juice which was confined in a bottle just like the shape of a ORS. So, when I was blowing the straw, the juice in the pack just backfired to me.
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Answers
Answer:
.” The liquid moves because of the difference in air pressure produced when you suck the air through the top of a straw while the bottom is in the liquid. The air pressure pushing on the surface of the liquid in the container is greater than the pressure inside the straw, and therefore, pushes the liquid up the straw.
When you remove straw from your mouth, a small amount of air may enter the top of the straw, slightly increasing the pressure within the straw. This is immediately accompanied by a slight drop in the level of the water within the straw. When you quickly place your finger on the top of the straw, the air in-leakage stops and a new equilibrium level is reached inside the straw. When you withdraw the straw from the liquid, the pressure difference between the atmosphere and the air inside the straw above the liquid, keeps the liquid inside the straw. All of this is dependent upon a small enough diameter of the straw and the cohesive attraction between the liquid atoms or molecules. The cohesive attraction among the water molecules keeps the water together, preventing liquid from flowing out the bottom of the straw. Alternate liquids will have different vapor pressures and cohesive attraction between their particles, and may allow air bubbles to flow up the straw and allow the liquid to “gurgle” out of the straw.