Buoyancy

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Buoyancy

• Important points to consider
•  
• The weight of an object can be expressed as

• If the object is fully submerged, V object V
  Displaced Fluid

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The Problem A downward force of 18 N must be
applied to an object weighing 480 N to keep it
fully submerged in water. Find the density of the
object.
We want to just keep is submerged and not
accelerate it upwards or downwards, so ? F 0.
Draw a free-body diagram of the object.
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We can describe the buoyant force as
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Because the object is fully submerged, this is
also the volume of the object. So, we need a
relationship between volume and density