Upthrust vs Weight: Object Immersion in Fluids

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AI Thread Summary
An object immersed in a fluid will sink if its weight exceeds the upthrust (buoyancy) and float if the upthrust is greater. When weight equals upthrust, the object achieves neutral buoyancy, meaning it neither sinks nor floats but remains suspended at any depth. This state is theoretical, as true neutral buoyancy can only occur if the object is identical to the fluid. The terms 'positive buoyancy', 'negative buoyancy', and 'neutral buoyancy' are essential for understanding these concepts. Overall, the relationship between weight and upthrust determines an object's behavior in a fluid.
MBBphys
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Homework Statement


Object immersed in fluid.
If weight larger than upthrust, it sinks. If less, it floats. If weight equal to upthrust, it floats, right?
Thanks!

Homework Equations


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The Attempt at a Solution


N/A
 
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That would constitute neutral buoyancy. In reality it could never quite happen (unless the object is a notional parcel of the fluid itself). It would not properly be described as either floating or sinking. It would just stay wherever it is put, as long as it is fully immersed. It could be touching the surface, touching the floor, or anywhere in between.
 
MBBphys said:

Homework Statement


Object immersed in fluid.
If weight larger than upthrust, it sinks. If less, it floats. If weight equal to upthrust, it floats, right?
Thanks!

Homework Equations


N/A

The Attempt at a Solution


N/A
If by 'upthrust' you mean buoyancy, the terms 'positive buoyancy', 'negative buoyancy', and 'neutral buoyancy' have specific meanings in this context.

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