2007-06-20 01:46:15 · 9 answers · asked by Anonymous in Science & Mathematics ➔ Physics
Water and air... A sub has ballast (water in tanks) that alllow it to submerge. When it wants to surface it blows out that water...
2007-06-20 01:48:55 · answer #1 · answered by mjvincent 3 · 0⤊ 0⤋
A submarine could be said to 'barely' float. It is designed to have a volume and weight so that the same volume of water weighs slightly more than the sub.
Now, by letting air (very low density) out of the ballast tanks and replacing it with water (a density close to 1), the over all density of the submarine becomes much closer to that of the water. Now, the boat has neutral bouyancy and can control its depth with its diving planes. In order to do this, the boat must be moving forward.
If the sub wants to return to the surface quickly, it forces the water out of the ballast areas and attains positive bouyancy. Now, it will float to the surface regardless of whether it is propelling itself through the water under power.
2007-06-20 09:02:29 · answer #2 · answered by tbolling2 4 · 0⤊ 0⤋
All surface ships, as well as surfaced submarines, are in a positively buoyant condition, weighing less than the volume of water they displace. To submerge hydrostatically, a ship must gain negative buoyancy, either increasing its own weight or decreasing displacement of the water. To control their weight, submarines are equipped with ballast tanks, which can be filled with either outside water or pressurized air.
2007-06-20 08:56:28 · answer #3 · answered by jsardi56 7 · 0⤊ 0⤋
Great question,
a submarine has a ballast (or a few i think) tank which operates exactly like the air bladder of a fish, when it wants to go down it blows the air out so it is a solid object (and very heavy) so it will sink, and for surfacing it sucks air in making it lighter and floatable.
upon saying this though i dont understand how they would suck air in out of a water environment... have to do some research there.
2007-06-20 08:52:06 · answer #4 · answered by chicalaloo 2 · 0⤊ 0⤋
When a submarine fills its ballast tanks with water, it renders the ship heavier than the same volume of seawater, thus allowing it to submerge. By pumping out the water, the ship is lighter than the amount of water it displaces, and is therefore bouyant.
2007-06-20 09:13:44 · answer #5 · answered by Treefrog 43 2 · 0⤊ 0⤋
A submarine has buoyancy tanks.
If she allows them to fill with water, she sinks. If she has them full of air, she rises.
Usually, pressurized air is used to empty out the water.
2007-06-20 08:50:57 · answer #6 · answered by Anonymous · 0⤊ 0⤋
it releases water from its tanks. the water in the submarine causes the submarine to stay submerged in the water
2007-06-20 08:49:40 · answer #7 · answered by Lyrad 2 · 0⤊ 0⤋
Simple, it fills it ballast tanks to sink and it lets it out to float. SImple right. Who was the genius who thought about that?
2007-06-20 08:55:29 · answer #8 · answered by UltimaFenrir28 3 · 0⤊ 0⤋
It pumps out water from its ballast tanks.
2007-06-20 08:49:08 · answer #9 · answered by Keiko 2 · 0⤊ 0⤋