2006-10-09 00:58:29 · 11 answers · asked by Leo Vic A 1 in Science & Mathematics ➔ Other - Science
It has to do with the buoyancy thing...
2006-10-09 01:01:10 · answer #1 · answered by Anonymous · 0⤊ 1⤋
A submarine or a ship can float because the weight of water that it displaces is equal to the weight of the ship.
This displacement of water creates an upward force called the buoyant force and acts opposite to gravity, which would pull the ship down. Unlike a ship, a submarine can control its buoyancy, thus allowing it to sink and surface at will.
To control its buoyancy, the submarine has ballast tanks and auxiliary, or trim tanks, that can be alternately filled with water or air.
When the submarine is on the surface, the ballast tanks are filled with air and the submarine's overall density is less than that of the surrounding water. As the submarine dives, the ballast tanks are flooded with water and the air in the ballast tanks is vented from the submarine until its overall density is greater than the surrounding water and the submarine begins to sink (negative buoyancy).
A supply of compressed air is maintained aboard the submarine in air flasks for life support and for use with the ballast tanks. In addition, the submarine has movable sets of short "wings" called hydroplanes on the stern (back) that help to control the angle of the dive.
The hydroplanes are angled so that water moves over the stern, which forces the stern upward; therefore, the submarine is angled downward.
To keep the submarine level at any set depth, the submarine maintains a balance of air and water in the trim tanks so that its overall density is equal to the surrounding water (neutral buoyancy). When the submarine reaches its cruising depth, the hydroplanes are leveled so that the submarine travels level through the water.
Water is also forced between the bow and stern trim tanks to keep the sub level. The submarine can steer in the water by using the tail rudder to turn starboard (right) or port (left) and the hydroplanes to control the fore-aft angle of the submarine.
In addition, some submarines are equipped with a retractable secondary propulsion motor that can swivel 360 degrees.
When the submarine surfaces, compressed air flows from the air flasks into the ballast tanks and the water is forced out of the submarine until its overall density is less than the surrounding water (positive buoyancy) and the submarine rises.
The hydroplanes are angled so that water moves up over the stern, which forces the stern downward; therefore, the submarine is angled upward.
In an emergency, the ballast tanks can be filled quickly with high-pressure air to take the submarine to the surface very rapidly.
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2006-10-09 05:10:05 · answer #2 · answered by Edis 2 · 0⤊ 0⤋
It floats when it displaces more water than the vessel weighs.
It sinks when it weighs more than the water it displaces.
It holds it's depth by maintaining an equal weight to displacement, and by moving through the water. It's bow planes (wings on the front) help maneuver it up and down.
This is all done by moving water inside and out of ballast tanks.
2006-10-09 01:07:02 · answer #3 · answered by tercir2006 7 · 1⤊ 0⤋
Subs can sink, rise, and float underwater (maintain "neutral buoyancy"). Subs do all this by adjusting the amount of water and air in their ballast tanks. When the tanks are full of air, the sub weighs less than the volume of water it displaces and it floats. When the ballast tanks are flooded with water, the sub weighs more than the water it displaces, and it sinks...
2006-10-09 01:07:53 · answer #4 · answered by Anonymous · 2⤊ 0⤋
They have boyancy tanks which they pump air into and so expelling water to go up, they allow water into these tanks to sink. The air is kept on board the submarine in high pressure tanks
2006-10-09 01:01:34 · answer #5 · answered by survival_paul 4 · 1⤊ 0⤋
Tanks within the vessel are filled with water to make it heavier and then filled with air to make it lighter. This gives it the ability to sink or float or anywhere in between.
2006-10-09 01:02:31 · answer #6 · answered by Letsee 4 · 1⤊ 0⤋
the sub form two shell chamber...these chamber fill with water that make SUB sink and pumb water out of these chamber that make SUB float....easy
2006-10-09 01:02:38 · answer #7 · answered by Anonymous · 1⤊ 0⤋
pressure tanks, they fill em with water if they wanna sink, and push compressed air into them if they wanna rise.
2006-10-09 01:01:44 · answer #8 · answered by Archangel 4 · 1⤊ 0⤋
C0URTNEY! u little brat! =/ i regarded up: submarine undertaking solutions & then i got here across u! its the evening in the previous its due and its approximately evening & i havent even began my undertaking yet! WAAHHH! =[
2016-11-27 02:17:17 · answer #9 · answered by Anonymous · 0⤊ 0⤋
They change their wight with water.
2006-10-09 01:06:48 · answer #10 · answered by DWReyes 3 · 1⤊ 0⤋