How does gauge pressure affect the buoyant force on a submerged object?

In summary, the buoyant force on a submerged object is determined by the weight of the fluid it displaces, which is affected by the density of the fluid. While density does increase with pressure, it only has a small impact on the buoyant force. The equation for relating gauge pressure to buoyant force is BF = density @ zero GP * Volume (1 + GP/EB), where EB is the bulk modulus of the fluid. This equation shows that gauge pressure has a minimal effect on the buoyant force, except at extreme depths.
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How can we relate gauge pressure (pg) to the buoyant force , in a completely submerged object?
is it as follow: Buoyant force= pg.Area +Density(water).volume.gravity ?
 
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How can we relate gauge pressure (pg) to the buoyant force , in a completely submerged object? is it as follow: Buoyant force= pg.Area +Density(water).volume.gravity ?

The buoyant force on a submerged object is equal to the weight of the volume of the fluid displaced. This weight depends on the density of the fluid. In so far as the density increases with pressure the buoyant force will increase. But density increases only very slowly for liquids which is determined by its compressibility which is determined by its Bulk Modulus. For water for example the density increases only a few percent at a depth of 20,000 ft, so the buoyant force will only increase by this amount. Gauge pressure will have increase from zero to over 9,000 psi at this depth. So the buoyant force can be related to gauge pressure by the equation

BF = density @ zero GP *Volume( 1 + GP/EB)

Where EB is the bulk modulus of the fluid: For water it is 3.1x105 lbs/in2

So you see GP makes negligible difference in BF except at extreme depths.
 

What is buoyant force and how does it work?

Buoyant force is the upward force exerted on an object submerged in a fluid (such as water or air). It is caused by the difference in pressure between the bottom and top of the object, with the higher pressure at the bottom pushing up on the object. This is also known as Archimedes' principle.

How is buoyant force calculated?

The buoyant force on an object is equal to the weight of the fluid displaced by the object. This can be calculated using the formula Fb = ρVg, where Fb is the buoyant force, ρ is the density of the fluid, V is the volume of the displaced fluid, and g is the acceleration due to gravity.

What is gauge force and how is it related to buoyant force?

Gauge force is the force exerted by a pressure gauge on an object. In the case of buoyant force, the gauge force is equal to the difference between the pressure at the bottom and top of the object. This difference in pressure is what causes the buoyant force to act on the object.

How does buoyant force affect the weight of an object?

Buoyant force can decrease the weight of an object when it is submerged in a fluid, as the upward force counteracts the downward force of gravity. However, the weight of the object will still be the same in terms of mass, as buoyant force does not affect an object's mass.

What are some real-world applications of buoyant force?

Buoyant force is important in many areas, including ship and submarine design, hot air balloons, and swimming. It also plays a role in determining the density and composition of objects, such as testing whether something is made of real gold or a cheaper material.

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