Question

how does a submarine move up and down in water body

Answer 1

In the surfaced position, the submarine’s displacement (the amount of water it displaces) is equal to the volume around the yellow part of the hull, and the maximum upthrust is created. The submarine has two hulls, an internal pressure hull and an external hull open to the sea at the bottom, with the openings at the top controlled by ballast valves. The space between is the ballast tank.

The submarine’s displacement is reduced by letting water into the ballast tanks that surround the pressure hull by opening the main vents at the top, such that the displacement (still the yellow portion) is reduced, thereby reducing the upthrust such that the weight of the submarine starts to overcome the upthrust keeping it up.

The displacement has been reduced to just the volume of the pressure hull, such that the submarine sinks further. By adjusting the amount of air (plus the hydroplanes when the submarine is moving), the depth can be varied from surface to its maximum safe diving depth. At any point in between, the submarine will “hover” at “neutral buoyancy”.

#BeBrainly

Answer 2

Answer:

when the ballast tanks are filled with air the submarine will go up. when the ballast tanks are not filled with air.