Explaining Everyday Phenomenons: Water Whirling and Rings in Tomato Juice

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Water swirls when flushed due to the design of toilet jets, which direct the flow to create a vortex for effective cleaning, rather than the Coriolis effect, which is only significant on a larger scale. When drinking tomato juice, rings form on the glass because of surface tension, which causes the liquid to cling unevenly and leave deposits in a ring pattern as the glass stabilizes. These phenomena illustrate basic principles of fluid dynamics and surface tension. Understanding these concepts can clarify why everyday occurrences behave in specific ways. Such insights can enhance appreciation for the science behind common experiences.
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Hi everyone!
I have two rather simple, everyday phenomenons that I can't explain.
1) Why does water whirl when you flush it down, why doesn't it go in a straight line?
2) When you're drinking tomato juice, then why are there rings on the glass (after every zip there remains some juice on the glass, but why isn't it "even" in every place but forms rings.)?

You don't actually have to write any complex math here, just a definite answer so that an high school student can understand it.
 
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Joonasja said:
Hi everyone!
I have two rather simple, everyday phenomenons that I can't explain.
1) Why does water whirl when you flush it down, why doesn't it go in a straight line?
2) When you're drinking tomato juice, then why are there rings on the glass (after every zip there remains some juice on the glass, but why isn't it "even" in every place but forms rings.)?

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You don't actually have to write any complex math here, just a definite answer so that an high school student can understand it.

First takes:

1. The "old wives' tale" that it is because of coriolus is wrong. That only works on the large scale. The jets are directed to cause a swirl to help clean the bowl.

2. The rings form when the glass is stabilized long enough for the layer of surface tension to leave deposits.
 
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