2007-05-21 10:28:33 · 15 answers · asked by Anonymous in Science & Mathematics ➔ Physics
Buyant force, a body which is completely or partially submerged in a fluid experiences an UPWARD force called the Buoyant Force , which is equal in magnitude to the weight of the fluid displaced by the object. This principle can be used to explain why ships, loaded with millions of kilograms of cargo, are able to float. Also, objects float better in salt water because it is denser.
2007-05-21 10:31:13 · answer #1 · answered by Yahoo! 5 · 2⤊ 1⤋
The mass of the water dispalced by the ship is more than the mass of the ship and so the ship floats (even after adding some cargo or people - upto a limit of course). If the same amount of steel was in the form of a sphere or a cube, it would sink since the mass would take less volume for a solid. By making the ship very hollow, its volume has been greatly expanded and so the displacement has been increased.
2007-05-21 17:33:25 · answer #2 · answered by Swamy 7 · 0⤊ 0⤋
Whether or not something sinks or floats is based on its density. Density is measured as the total mass divided by the total volume. For a steel ship, the outer parts are made of steel, but all of the inside is full of air. So the overall mass of the ship is still pretty small compared to the volume.
Ships float because their density is less than that of water. I hope that made sense.
2007-05-21 17:33:36 · answer #3 · answered by Brooke 3 · 0⤊ 0⤋
In order for the steel ship to sink, its density has to be greater than the liquid in which its in. If a ship sails from fresh water into salt water it floats higher, just as it is easier for you to float in an ocean than in a lake. Although steel is denser than water, a ship's bowl-like hull displaces enough water to allow it to float, as long as it's not overloaded. There is a boundary in the area of the hull called the Plimsoll line, which indicates where the ship should ride in the water for safe maximum load. The same concept is true for hot-air balloons.
2007-05-21 17:39:29 · answer #4 · answered by Astromaniac 4 · 0⤊ 0⤋
Hey,
I used to live on a Steel Sailboat. This was one of the first questions I asked when I moved on to the boat.
The boat will float as long as it has enough volume to displace an amount of water equal to its own weight. (this is most evident in container ships that add water as weight to its Bilge when it has light to no cargo) Its weight, or the force of gravity, will equal its buoyancy, or the force of the water pushing up on it.
All steel boats have Zinc weights that attach to the hull.
If these were not in place, the salt and sea water would rust and damage the vessel very quickly. The Zincs are sacrificed to the elements and are attacked by the rust before it causes damage to the hull. The Zincs should be changed evey 12 months, in order to discourage rust to the boat.
2007-05-21 18:30:19 · answer #5 · answered by SherrySherry 1 · 1⤊ 0⤋
Volume of a ship must be greater than the volume of water, so that is why ships don't sink. This the ship as a body of warm air and the water is cold air. One is denser the other, and this is the idea for ships. Also want to note that water is a high polar molecule and the bond between the oxygen and hydrogen is strong, so that can contribute why ships float on water.
2007-05-21 17:39:55 · answer #6 · answered by Invisble 4 · 0⤊ 1⤋
A ship displaces water (takes up the water's space). As long as the water it displaces weighs more than the ship, it will float. A steel ship is hollow, so it weighs less than the water it displaces. If the ship were solid, it would sink.
2007-05-21 17:32:18 · answer #7 · answered by TychaBrahe 7 · 0⤊ 0⤋
An object, whose mean density is greater than that of water, will sink.
If the mean density is less than that of water, itwill float. The density of steel is somewhere around 10-15g/cm^3, probably. Let us assume 15...
Water is 1g/cm^3.
But we have to take the mean density. Inside ships is a lot of air, which weighs only a little, about 0.001 g/cm^3, we can take that it is equal to 0...
so, for the mean density of the ship to be less tha that of water, for each cubic metre of steel, we need at least (preferably more than) 14 cubic metres of air. If we have, say 19 cubic metres of air for 1 cubic metre of steel, we would get the mean density (roughly)
d=(1*15+19*0.001)/(1+19)=0,77g/cm^3.This is less than water, so such a ship will float, with about 3/4 of it below water. If we increase the air:steel ratio, we make the ship rise higher out of the water.
So, the trick is that ships carry enough air inside them to let them stay afloat, despite all the steel.
2007-05-21 17:55:21 · answer #8 · answered by misiekram 3 · 0⤊ 0⤋
Both wood and steel ships sink.
2007-05-21 17:46:05 · answer #9 · answered by Anonymous · 0⤊ 0⤋
A steel ship floats on water because it’s not made of solid steel. If its made of solid steel, it will sink. Bouyancy make ships to float.
2007-05-21 17:38:52 · answer #10 · answered by OhSnap! 1 · 0⤊ 0⤋