How Does Depth Affect the Buoyant Force on a Submerged Beach Ball?

AI Thread Summary
As a beach ball is submerged deeper in water, the buoyant force does not remain constant due to the compressibility of the gas inside it. Archimedes' principle states that the buoyant force equals the weight of the displaced water, but as the ball descends, the increased pressure causes the ball's volume to decrease. This reduction in volume leads to a decrease in the amount of water displaced, which in turn reduces the buoyant force acting on the ball. If the ball were rigid, the buoyant force would remain unchanged. Therefore, the depth affects the buoyant force by altering the volume of the beach ball.
whattheheckV
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A beach ball is made of thin plastic. It has been inflated with air, but the plastic is not stretched. By swimming with fins on, you manage to take the ball from the surface of a pool to the bottom. Once the ball is completely submerged, what happens to the buoyant force exerted on the beach ball as you take it deeper?



Now I know that Archimedes' principal states that the buoyant force is equal to the weight of the displaced water. This is a multiple choice question and I choose that the buoyant force remains the same, and it said i was wrong. All help appreciated.
 
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Hi whattheheckV. http://img96.imageshack.us/img96/5725/red5e5etimes5e5e45e5e25.gif

Pearl divers found that the deeper they went, the greater the pressure.
 
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I'll give you a tip: gas is compressible.
 
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Hi WhattheheckV. Welcome to Physics Forums!

If a submarine goes too deep, its hull gets crushed. As you go deeper with the beach ball, its surface starts to wrinkle and buckle, and, as a result, its volume decreases. (If the beach ball were rigid, its volume wouldn't change, the buoyant force would remain constant).

Chet
 
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