Gravity and Helium: Why Does Helium Float Up?

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Discussion Overview

The discussion revolves around the question of why helium floats in the air despite gravity applying a force to all objects. It explores concepts related to buoyancy, density, and gravitational force, with references to both helium and other materials like wood in different contexts.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant questions how helium can float if gravity applies the same force to all objects, suggesting a misunderstanding of the relationship between gravity and buoyancy.
  • Another participant notes that helium will not float in a vacuum or thin air, implying that the surrounding medium affects buoyancy.
  • A different perspective is offered, stating that helium floats because it is in air, which has a higher density than helium, and that the gravitational force on the air is greater, thus "pushing" the helium up.
  • One participant introduces a parallel question about wood floating in water, suggesting that the principles of buoyancy may apply similarly to different materials.
  • A note is made that while gravity creates a uniform field, it does not apply the same force on all objects, hinting at the complexity of the situation.

Areas of Agreement / Disagreement

Participants express differing views on the nature of gravity's effect on objects and the role of density in buoyancy. There is no consensus on the explanation of why helium floats, and multiple competing views remain present.

Contextual Notes

Some assumptions about the nature of gravity and buoyancy are not fully explored, and the discussion includes varying definitions of how gravitational force is perceived across different materials.

DB
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If gravity aplies the same force on every object, accellerating it to about 10 m/s2 (gee), then how come for example helium floats up to the sky?

Thnx
 
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DB said:
If gravity aplies the same force on every object, accellerating it to about 10 m/s2 (gee), then how come for example helium floats up to the sky?

Thnx

Hint: the helium balloon will NOT float up the sky if it is in a vacuum, or very thin air.

Zz.
 
Because it is "in the sky"- in other words, in air that has a higher density than helium has. The air is attracted by a greater force than the helium is (gravitational force is proportional to the mass) and "pushes" the helium up.
 
DB said:
If gravity aplies the same force on every object, accellerating it to about 10 m/s2 (gee), then how come for example helium floats up to the sky?

Thnx

Hope this isn't too many cooks...

Try this : If gravity applies the same force on every object, accellerating it to about 10 m/s2 (gee), then how come for example wood floats up to the top of a lake ?

NOTE : Gravity does not apply the same force on all objects, it creates the same field (at some height)...but that's not important here.
 

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