2007-01-31 04:43:40 · 11 answers · asked by Anonymous in Science & Mathematics ➔ Engineering
It's the dimensions. A ship is made of steel, but it's not as dense as a flat piece, and that's why it doesn't sink, I think. I don't think they'd have the same mass though. Because is mass is like volume per area or something like that and a piece of steel would be more dense.
2007-01-31 04:49:43 · answer #1 · answered by true blue 6 · 0⤊ 1⤋
Hi,
As others have said it is the displacement of the water that causes floatation, the vessel has to displace more weight of water than its own weight, eg.
A hollow tin can when sealed will bob like a cork on the water, open the can, fill it with water and it will sink very quickly, not because of the weight of the water but because the mass of the metal is heavier than the mass of the water.
to check this take a used tin can and weigh it empty, note the weight, fill the can with water and re-weigh it,calculate the extra weight and that result is approximately the amount of water it can displace if pushed under.
As the difference is great, the can will bob like a cork, as opposed to a submarine where the displacement is controlled to make the sub' rise or sink.
I hope this helps
2007-02-03 20:18:53 · answer #2 · answered by Brian E 2 · 0⤊ 0⤋
The phenomenon is governed by Archimedis' priciple which is, when mass of the water displaced by a body immersed in water is greater than the body it floats if it is less then the body sinks. When a physical body is immersed in water the gravity pulls it down and the bouyancy of water pushes it up acting in the direction opposite to the gravity. The net resultant force determines if the body floats or sink. When bouyancy is more it floats otherwise sinks. The same principle applies to a flying aircraft where the medium is air instead of water.
2007-02-01 08:08:10 · answer #3 · answered by Oracle 1 · 0⤊ 0⤋
Water displacement is the key. Think of it this way: the part of the boat which is under water is mostly hollow and contains mostly air. Air doesn't weigh much at all compared to water. So the boat is displacing a volume of water with mass equal to the entire boat, but volume equal to the steel/air portion which is under the surface.
2007-01-31 12:55:15 · answer #4 · answered by Yamson 3 · 0⤊ 0⤋
It's all about how much water is displaced (pushed away).
A flat piece of metal displaces very little water. Metal is usually much denser than water, so it sinks.
But take the same metal made thinner and curve it up, the water displaced (by air) will make it float.
The same thing holds true for floating in air, only there we displace air by something even lighter, like helium.
2007-01-31 13:02:41 · answer #5 · answered by Jim 7 · 0⤊ 0⤋
it's all ball bearings. (sorry, a fletch quote. ;o)
it's all about displacement. boat will displace water and not allow water go over the sides, thereby causing buoyant forces to counterat gravity. a flat piece of steel will allow the water to go over the top and negate the buoyant forces, just leaving gravity.
2007-01-31 13:03:05 · answer #6 · answered by bsah 3 · 0⤊ 0⤋
The shape of the boat causes it to displace more water than the space the boat encompasses in the water. This causes it to be buoyant or to float.
Hope this helps.
2007-01-31 12:47:28 · answer #7 · answered by squang 3 · 1⤊ 0⤋
Water displacement with the shape of the metal.
2007-01-31 12:50:21 · answer #8 · answered by psionne 3 · 0⤊ 0⤋
bouyancy....
water exerts a pressure against the hull of the boat to keep it afloat.
basically, the weight of the displaced water = the bouyant force keeping the ship afloat.
2007-01-31 12:48:54 · answer #9 · answered by Anonymous · 1⤊ 0⤋
I've heard of people making reinforced concrete boats.
Just to prove the principle of displacement, which I reckon goes back to good old Archimedes.
2007-01-31 14:47:39 · answer #10 · answered by efes_haze 5 · 0⤊ 0⤋