don't know the actual record, but i know that the USS Parchee was "submerged" for 87 days in 1985/86(?).
The record for a submarine being continuously underwater is held by the USS Pennsylvania, a nuclear-powered submarine that submerged for 140 days during a patrol in 2019.
Being, acting, or growing, under water in the sea; as, submarine navigators; submarine plants., A submarine plant or animal.
your simply being rude.
Sylvia Earle was born in 1935. She designed a small submarine for underwater exploration. She started a business called Deep Ocean Engineering which builds the small submarines, which can reach 35,000 feet, the deepest ocean depth known.
Hutton, Hutton is credited with being the founder of modern geology. Among his ideas: The Earth is continually being formed.
In war a submarine can hide under the water and attack without being seen.
Underwater explosives (depth charges, torpedoes, submarine sinkers, etc) are just designed to successfully explode, just like any other bomb. Being in water doesn't affect a bomb too much, as long as the explosive material doesn't get wet, as well as any electronic detonating systems. In other words, an underwater explosive is just like any other explosive, but just waterproof.
1956
There are many items underwater that are found in many places.
A submarine rotates its turbines in the opposite direction of normal rotation to cause water to be drawn towards the submarine. The force causing the mass to be moved toward the bow of the submarine is counteracted by the force drawing the submarine backwards.
Being underwater does not feel the same as being wet when exposed to the air, because when you are underwater the water on your skin is not evaporating, and doesn't make you feel cold. Nonetheless, a person underwater is wet, even though he or she won't really feel wet.
by being cold blooded by having second eyelids and by being able to breath underwater
Thanks to Physics