Buoyant Force - Clarification

[EZR]

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I'm reading this from TBR, Page 62 (Book 2)

For a floating object:

W=B
pobject * Vobject = pmedium * Vdisplaced
Vdisplaced / Vobject = pobject * pmedium
Vobject > Vdisplaced ; pobject < pmedium


My question is why wouldn't Vobject = Vdisplaced?

In the book example preceding ^ all of that... the answers states:
The buoyant force a fluid exerts on an object is (B = pfluid * Vdisplaced * g). Because Ball A has the same volume as Ball C, they experience the same buoyant force. The reason Ball A sinks and Ball C floats has to do with their differences in weight, despite that they experience the same buoyant force.

^That answer seems to support my understanding that Vobject = Vdisplaced. The description, however (top part) states the object's volume is less than the volume of fluid that's displaced. How?

Thanks in advanced.

 

[milski]

Vobject=Vdisplaced means that the object is completely submerged under water. At that point either the density of the object is higher than the density of the fluid and it will sink, or it is exactly the same and the object will stay at whatever depth it is moved by any other force.

 

[folktale]

Just think about it on simple terms. If an object floats, why would it be that Vdisplaced = Vobject? Some of the object is above the liquid it's floating on. For example, if 85% of the object is submerged, there is 85% of the liquid displaced as well. If Vdis=Vobj, then 85%(displaced fluid) =100%(object volume)?? It's just not right.

But if it's completely submerged, then you can say that Vdis=Vobj since 100% of the object is in the fluid.

 

[EZR]

If Vdis=Vobj, then 85%(displaced fluid) =100%(object volume)?? It's just not right.

But if it's completely submerged, then you can say that Vdis=Vobj since 100% of the object is in the fluid.

Then why is the buoyant force the same for a sunken object and a floating object (Ball A and C)?

 

[folktale]

Then why is the buoyant force the same for a sunken object and a floating object (Ball A and C)?

Even though they have the same volume, they have different densities.

 

[EZR]

Even though they have the same volume, they have different densities.

Thanks. I get it. I don't know why I was so confused.