Why does water or balls spill out ?

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Discussion Overview

The discussion revolves around the question of why liquids, like water, and small objects, such as balls, spill out when a container is removed or opened. Participants explore concepts related to gravity, potential energy, and the behavior of materials in relation to forces acting upon them.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant expresses confusion about why water spills when a cup is removed, questioning if gravity is the cause, despite it being a downward force.
  • Another participant suggests that there is a tendency for a net reduction of potential energy, implying that this might explain the spilling behavior.
  • There is a discussion about the components of gravitational force, particularly in relation to inclined surfaces, which may influence how objects behave when a container is opened.
  • A participant introduces the concept of the angle of repose, noting that different materials have distinct angles that affect their stability and spilling behavior.
  • Entropy is mentioned as a factor, with the idea that the universe tends towards equilibrium, which could relate to the spilling of materials.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the primary reason for the spilling behavior, with multiple competing views presented regarding the roles of gravity, potential energy, and material properties.

Contextual Notes

Some participants reference specific concepts like the angle of repose and entropy, but the discussion remains open-ended with no definitive conclusions drawn about the mechanics involved.

Sunanda Goh
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I know, this is a very stupid question, but it troubles me the whole day and i can't figure it out.
Why can't water remains its shape if the cup is being removed and the water will spill all over the table ?
And if you fill your car with full of small balls and when you open the door of your car, the balls spill out too ?
Is it Gravity or ? But isn't gravity a downward force ?
Forgive me stupidity
 
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There is a "tendency" for net reduction of potential energy (height above ground level).
 
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Sunanda Goh said:
I know, this is a very stupid question, but it troubles me the whole day and i can't figure it out.
Why can't water remains its shape if the cup is being removed and the water will spill all over the table ?
And if you fill your car with full of small balls and when you open the door of your car, the balls spill out too ?
Is it Gravity or ? But isn't gravity a downward force ?
Forgive me stupidity
What's the matter with gravity being a downward force? Do the balls spill out of your car in an upward direction when you open the door?
 
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SteamKing said:
What's the matter with gravity being a downward force? Do the balls spill out of your car in an upward direction when you open the door?

Nope. That's why I'm asking if it's Gravity.
 
You might be interested in reading about angle of repose.

https://en.wikipedia.org/wiki/Angle_of_repose

Every material has its distinct angle of repose - as any sand castle builder knows.
I encountered this yesterday, while trying to dig down into the blown cellulose insulation in my attic.

Water has an AR of 0. :)
Round balls would have a variable AR, depending on how orderly-stacked they might be.
 
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DaveC426913 said:
You might be interested in reading about angle of repose.

https://en.wikipedia.org/wiki/Angle_of_repose

Every material has its distinct angle of repose - as any sand castle builder knows.
I encountered this yesterday, while trying to dig down into the blown cellulose insulation in my attic.

Water has an AR of 0. :)
Round balls would have a variable AR, depending on how orderly-stacked they might be.

Woah ! Thanks !
 
Or you could just say Entropy - the universe tends towards equilibrium in all things.
 

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