What Force is Necessary to Submerge Mary in Fresh Water?

In summary, specific gravity is the ratio of density of a substance to the density of water. Weight in air is the force exerted on an object by Earth's gravity when it is in the air. The force necessary to barely submerge an object is equal to the weight of the water displaced by the object and is related to specific gravity. Factors that can affect this force include the density and shape of the object, the density of the surrounding fluid, and the strength of gravitational force.
  • #1
coopertown
2
0
What force is necessary to just barely submerge (push Mary under fresh water) Mary if her average specific gravity is 0.95 after taking a deep breath and her weight in air is 660 N?


F=mg ; Force of buoyancy=ρgV;



F=mg
660/9.8=mass of air
mass of air=67.3
force of buoyancy= 67.3 x 0.95
=63.94 Newtons

is this right?! i am panicking! physics is so hard omg. fluids are so difficult to understand! waaaaaaaaa
 
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  • #2


Do not panic! You have the formula for the buoyant force

Force of buoyancy=ρgV.

What do ρ, g, V mean?

ehild
 

FAQ: What Force is Necessary to Submerge Mary in Fresh Water?

What is specific gravity?

Specific gravity is the ratio of the density of a substance to the density of a reference substance, usually water.

What is weight in air?

Weight in air is the force exerted on an object by the Earth's gravity when it is in the air.

What is the force necessary to barely submerge an object?

The force necessary to barely submerge an object is equal to the weight of the water displaced by the object. This is known as Archimedes' principle.

How is specific gravity related to the force necessary to barely submerge an object?

Specific gravity is directly related to the force necessary to barely submerge an object. The higher the specific gravity of an object, the greater the force needed to submerge it.

What factors can affect the force necessary to barely submerge an object?

The force necessary to barely submerge an object can be affected by factors such as the density and shape of the object, the density of the surrounding fluid, and the strength of the gravitational force.

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