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Bowling for Seabed Grime

Bowling for Seabed Grime

Posers and Puzzles

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Originally posted by royalchicken
Bingo. So when we talk about a ball displacing its mass worth of water (in the boat), and its volume worth (in the water), which is the bigger displacement?
It would seem that the weight of the ball would be a factor in that. I don't know what a normal weight is; I play with a 22 pound ball. But intuitively, I would say I feel that the volume would be the bigger displacement.

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Are you sure? Remember, the volume of the ball is less than a piece of water of the same weight.

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Originally posted by royalchicken
Are you sure? Remember, the volume of the ball is less than a piece of water of the same weight.
Again, it's been a while since I studied this kind of stuff, I can't really remember at this point.

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Originally posted by Cheshire Cat
Just a thought, but it would seem that, being a solid, the ball by definition would have to be denser than water, which as we know is a liquid.
the bowling ball is denser than water, but it's wrong to assume that any solid is denser than water. For a start, ice is less dense than water. I'm sure there's many other solids with a density less than 1.

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Originally posted by royalchicken
I take a standard bowling ball. I get into a rowboat with the bowling ball and row out into a lake. I then toss the ball overboard. What happens to the water level of the lake?
Archamedes (sp?) Chucks the ball back at you then builds a lever, flings it over a fulcrum and hoists you, the ball and the boat back onto the shore using only a tenth of the energy it took you to row out and chuck the ball! Shouting, "Have a little consideration here! We're dead and sleeping on the bottom. What's with the ball thing anyway? Hoy! " mumble mumble mumble.

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Originally posted by belgianfreak
the bowling ball is denser than water, but it's wrong to assume that any solid is denser than water. For a start, ice is [b]less dense than water. I'm sure there's many other solids with a density less than 1.[/b]
I find this information interesting. Could you point me to some more on this subject?

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Originally posted by royalchicken
I take a standard bowling ball. I get into a rowboat with the bowling ball and row out into a lake. I then toss the ball overboard. What happens to the water level of the lake?

Nothing at all. 😵

IvanH.

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When the bowling ball is floating (in the boat) it displaces its equivalent weight of water, when it is sunk to the bottom it displaces its own volume of water. Since a bowling ball is denser than water its weight of water is more than its volume of water - so the water level goes down.

However, what if the bowling ball was made of ice?

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Originally posted by iamatiger
When the bowling ball is floating (in the boat) it displaces its equivalent weight of water, when it is sunk to the bottom it displaces its own volume of water. Since a bowling ball is denser than water its weight of water is more than its volume of water - so the water level goes down.

However, what if the bowling ball was made of ice?
Arrgh, you beat me to it. No change in water level if the ball is made of ice. Finally, what if the bowling ball is less dense than air?

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Originally posted by Acolyte
Arrgh, you beat me to it. No change in water level if the ball is made of ice. Finally, what if the bowling ball is less dense than air?
The boat sinks a bit and therefore the water level goes up if the bowling ball floats away into the air, because the bowling ball was actually lifting the boat out of the water a bit.

Re. ice bowling ball - what if the lake was salty?

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Hi Mark,

The water level will go down.
The heavier the bowling ball, the more the water level of the lake goes down.

What will happen to the water level of the lake when you're sitting in the same boat and you let go of a balloon
filled with a gass lighter than air ? More or less the same story or ... ?

The water level will go up.

Joe.

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Originally posted by iamatiger
The boat sinks a bit and therefore the water level goes up if the bowling ball floats away into the air, because the bowling ball was actually lifting the boat out of the water a bit.

Re. ice bowling ball - what if the lake was salty?

Ice contains much less salt than salty water does, but that does not matter. As long as the ball in question floats on the water, the water level will not change when you throw the ball overboard. When it sinks or when it goes up like a balloon does, then the water level will change.

Joe

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Originally posted by ivanhoe

Ice contains much less salt than salty water does, but that does not matter. As long as the ball in question floats on the water, the water level will not change when you throw the ball overboard. When it sinks or when it goes up like a balloon does, then the water level will change.

Joe

Ok so far - but the ice bowling ball will gradually melt - what will happen to the lake then?

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Originally posted by iamatiger
Ok so far - but the ice bowling ball will gradually melt - what will happen to the lake then?

Nothing at all. 😵

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Even when the loch ness monster would come out of his hiding and completely shred your boat the water level would not be any different!