If battle ships are made of steel how do they stay afloat?

Answer 1

for something to float it must displace more weight in water than it weighs itself....so if a boat displaces 5000Lts of water
it must weigh less than 5000Kgs

A box that is made of steel that is 5 meters by 2 meters by 1 meter...has a volume of 1000 liters..so if it weighs less than 1000 Kgs...about 2000 Lbs..it will float..

Answer 2

Ships are heavy, but they're also huge, and not just a big, solid chunk of metal. There is plenty of "space" in a boat or ship or barge. This space is filled with air, which we know is lighter than water.
This leads to the discussion of two concepts; displacement and buoyancy.

Displacement refers to the volume of water the ship displaces (moves out of the way) or the weight of the water displaced - depending on context.

Buoyancy - as "discovered" by Archimedes is what actually makes the boat/ship float. This is the upward force applied by the water. (The water is trying to fill the void created when the ship displaces the water, so it's pusing against the hull.)

The boat only displaces water equal to its weight. If you've taken a statics class this is easy to figure out. Forces have to be balanced or else the object moves until equilibrium is achieved. The weight of the vessel is equal to the weight of the water the hull is displacing. However the boat has reserve buoyancy - typically on a small boat that means that the vessel sits high enough in the water that adding extra weight (thereby lowering the boat in the water) does not cause the edges of the hull to sink dangerously close to the water level. In larger vessels there are water tight tanks, called ballast tanks, which can be filled with water or emptied to adjust the weight of the vessel. this maintains the displacement of the vessel even as it changes the weight of cargo it is carrying.

Answer 3

You've got some correct but difficult answers and Easy Going's gotcha goin.

I'm an Empirical person but Metrics is good when converting. 1 Cubic Meter = 1 Kilo Litre (don't know the abbreviation, but it's 1,000 litres) = 1 Tonne (1,000 kg, Kilograms)

In the example the boat is 5m x 2m x 1m = 10 Cubic Meters.
10 Cubic Meters of water would weigh 10 tonnes.
If the 10 Cubic Meter boat weighed 2 tonnes, 20% of it would be below water and 80% above the water. It would settle 0.2 meters (20% of one meter) or 20 cm into the water.

Anything with dry volume that is set on water will either float if it's lighter than the same volume of water or sink if it's heavier than the same volume of water.

So in your case of the Battle ship assuming if it weighs 1,000 tons but its hull presents a volume greater than 1,000 cubic meters it will float. But it will displace, move aside, 1,000 cubic meters of water.

Answer 4

For an object to float, it must be able to diplace as much water as it's own weight. If the ship weighs 1000 tons, than the hull would have to displace 1000+ tons of water. If the volume of the hull occupies less than that amount of water, the ship will sink.

Answer 5

Yes, as all the answers above, this is the force of displaced water by the ship's hull squeezes the ship up.

Did you know that some ships hulls are made of concrete? Pretty bizzarre, isn't it? But it's true.

Answer 6

buoyancy

"In physics, buoyancy is the upward force on an object produced by the surrounding fluid (i.e., a liquid or a gas) in which it is fully or partially immersed, due to the pressure difference of the fluid between the top and bottom of the object. The net upward buoyancy force is equal to the magnitude of the weight of fluid displaced by the body. This force enables the object to float or at least to seem lighter. Buoyancy is important for many vehicles such as boats, ships, balloons, and airships."

Answer 7

Its average density is still much less than the density of water because of all the empty space inside the ship. Now how does the ocean "know" that its density is greater than the ship's and lets it float is an other question. You should look up the Archimedes Principle for that.

Answer 8

dont get all confused imaginig boyancy and "forces" pushing up.......although all those answers are correct........think of it this way.......steel weighs more than water, but a ship's hull encloses a lot of air which weighs a lot less than water....average out the steel in the ship with the air in the ship and you get a structure that on the average, weighs less than water so it floats.........

Answer 9

It's called DISPLACEMENT.

The amount of water that they displace (mass) is less than their volume.

In other words, if you had the same volume of water as the volume of the ship, the water would weigh more.
.

Answer 10

I thought they were made of plastic....Oh those are the ones in my bathtub

two words...WATER....DISPLACEMENT....