Density question - can a heavy object float in water ?

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Discussion Overview

The discussion revolves around the question of whether a heavy object, specifically a large ball weighing 100kg, can float in water. Participants explore concepts of density, buoyancy, and the conditions under which objects float, considering both theoretical and practical implications.

Discussion Character

  • Exploratory, Technical explanation, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant questions if a 100kg ball with a diameter of 1 meter would float, suggesting that as long as the object is less dense than water, it should float regardless of its weight.
  • Another participant asserts that an object will float if it weighs less than the water it displaces when submerged, emphasizing the importance of average density.
  • A third participant notes that boats, which can be heavier than 100kg, float, implying that weight alone does not determine buoyancy.
  • Further clarification is provided that a cubic meter of water weighs 1000kg, reinforcing the idea that density is the key factor for floating, not just total mass.

Areas of Agreement / Disagreement

Participants generally agree on the principle that density determines whether an object will float, but there are nuances in how this principle applies to different scenarios, leading to some debate about specific cases.

Contextual Notes

The discussion does not resolve the complexities surrounding buoyancy and density, particularly in relation to varying shapes and materials of objects.

Who May Find This Useful

Individuals interested in physics, particularly concepts related to buoyancy and density, may find this discussion relevant.

Yoann
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Would a big ball weighing 100kg with a diameter of 1 meter float in water?

I guess my question is, no matter how heavy an object might be, as long as it is less dense than water, it will float no matter what, right? Like even if that ball were made of a thick layer of steel (a few inches), as long as it is hollow/empty on the inside (and big enough so that its density is lower than water's), it would float, wouldn't it?

Thanks!
 
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As long as the object weighs less than the water it would displace if submerged, it will float. So yes, as long as the density of the object, including any hollow areas, is less on average than water it will float.
http://en.wikipedia.org/wiki/Buoyancy
 
Boats can float and I'm pretty sure they are heavier than 100kg's
 
That's what I thought, thanks for the replies! (and the link to Wikipedia, Drakkith! It's helpful)
 
Gravitational said:
Boats can float and I'm pretty sure they are heavier than 100kg's
Okay, but a cubic meter of water is a thousand kg.

The key is the density, not the total mass. If you include the air inside the boat then it is less dense than water, therefore it floats.
 

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