Test your buoyancy understanding!

[tomfcrist]

I think the better question should be directed back to the OP.......what differance does it make the level of the pool, when discussing bouyancy IQ? All you really need to know is that when you drop the damn rock the canoe/kayak will be more bouyant. The level of the water in the pool is so far detached from the concept of bouyancy that this question is just rediculous. Why not ask what happens to the boyancy of the canoe/kayak when you pour 6 tons of dirt into the pool?

 

[windapp]

i believe you are right so long as the weight is attached to the boat by a rope. cut the rope and the things change, because the excess neg bouyancy is not transfered to the boat. cant comment on the force diagram, however no rope was in the example . as it is throw the weight ovverboard and the pool level will drop. your answer is correect for your example but not the one given.

Actually, it doesn't matter if the weight is in the boat or attached by a rope (assuming the rope contribution to the weight is negligable). The key to solving either problem easily, and seeing they are one and the same is to black box the rock/boat system. An object or system of objects will displace a volume of water equivalent to its weight. When you look at it this way, the exact location of the rock is irrelevant as long as it, and the boat are floating together.

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I think the better question should be directed back to the OP.......what differance does it make the level of the pool, when discussing bouyancy IQ? All you really need to know is that when you drop the damn rock the canoe/kayak will be more bouyant. The level of the water in the pool is so far detached from the concept of bouyancy that this question is just rediculous. Why not ask what happens to the boyancy of the canoe/kayak when you pour 6 tons of dirt into the pool?

It was really an Engineering question rather than a diving question, but it was fun to answer

 

[tomfcrist]

It was really an Engineering question rather than a diving question, but it was fun to answer

I understand that......so why is the thread named "test your bouyancy understanding"????? The answer to the question has very little to do with bouyancy......just displacement.

 

[windapp]

I understand that......so why is the thread named "test your bouyancy understanding"????? The answer to the question has very little to do with bouyancy......just displacement.

The answer has everything to do with buoyancy. It just isn't applicable to diving.

 

[NAM001]

windcap ... it does matter you try this get a glass fill it and put a 1 # led weight in it and see if it displaces 1# .... it wont. your positon is correct till the point it submerges.. at that point weight hs no factor only the volumn of the object.

Actually, it doesn't matter if the weight is in the boat or attached by a rope (assuming the rope contribution to the weight is negligable). The key to solving either problem easily, and seeing they are one and the same is to black box the rock/boat system. An object or system of objects will displace a volume of water equivalent to its weight. When you look at it this way, the exact location of the rock is irrelevant as long as it, and the boat are floating together.

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It was really an Engineering question rather than a diving question, but it was fun to answer

 

[windapp]

Attach the weight to something floating and it will displace 1 # of water. It is the extra bit of sunk canoe that takes up the volume. Again, a floating object or system of objects always displaces its own weight of water. Grouping the rock and canoe rather than separating them into two parts during the floating phase simplifies the solution.

 

[tomfcrist]

Windapp, it really doesn't have much to do with buoyancy. The buoyancy of the canoe is irrelevant, it's displacement is.

 

[Insta-Gator]

http://www.gsseser.com/NIE/PDFs/Buoyancy.pdf

buoyancy, density, volume, displacement