Advice 1: Why ships don't sink

It seems amazing that the huge ocean ships staying afloat and not drowning. If you take a solid piece of metal and place it in the water, it will immediately sink to the bottom. And in fact modern liners are made from metal. What could possibly be good buoyancy? The fact that the metal hull of the ship is able to stay on the surface of the water, due to the laws of physics.
Why ships don't sink

Why not sink the ship

The ability to float on the water surface are characterized not only by ships, but also some animals. Get at least the front. This insect family Hemiptera feels confident on the water, moving through it sliding movements. This buoyancy is due to the fact that the tips of the legs of water striders cover hard hairs, which are not wetted by water.
Scientists and inventors hope that in the future people will be able to create a vehicle that will move through the water on the principle of Gerridae.

But in relation to traditional courts principles of bionics do not work. To explain the buoyancy of the ship made of metal parts, can any child familiar with the basics of physics. As stated in Archimedes ' principle, a body which is immersed in a liquid, it begins to act repulsive force. Its value is equal to the weight of water displaced by the body when diving. The body will not be able to drown if the Archimedes force exceeds the weight of the body or equal. For this reason, the ship remains afloat.

The greater the body volume, the more water it displaces. Iron ball, lowered into the water, immediately sink. But if you roll out to the state of the thin sheet and make it hollow inside the ball, this design will float on the water, only slightly immersed in it.

Vessels with a metal shell are constructed in such a way that at the moment of immersion of the hull displacing a very large amount of water. Inside the ship's hull has lots of empty spaces filled with air. Therefore, the average density of the ship is much less than the density of the liquid.

How to maintain buoyancy of the vessel?

The ship afloat until his plating intact and has no damage. But the fate of the vessel would be jeopardized, should he get a hole. Through a hole in the casing inside of the ship begins to enter the water, filling his inner cavity. And then the ship could sink.

To maintain the buoyancy of the vessel upon receipt of holes, its interior is split by a partition. Then a small hole in one of the compartments did not threaten the overall survivability of the vessel. From the compartment that has been flooded, the pumps pumped water, and the hole tried to close up.
Worse, if damaged in several compartments. In this case, the ship could sink due to loss of balance.

In the beginning of XX century Professor Krylov suggested deliberately flooding compartments located in part of a vessel which is opposite to the cavities that were subjected to flooding. The ship however, several were okazyvala in the water, but remained in a horizontal position and could not drown in the result of turning over.

Offer a marine engineer was so unusual that for a long time did not pay attention. Only after the defeat of the Russian fleet in the war with Japan, his idea was adopted.

Advice 2: Why ships sink

Modern ocean liners in their characteristics differ from those of sailing ships that plied the sea a few centuries ago. It would seem that current technology needs to ensure the ships a high survivability and floodability. However, and now ships from time to time sink. The causes of Maritime disasters can be very different.
Why ships sink
Modern vessels equipped with the most advanced navigation systems. The materials from which made the hull of ships, high durability, resistance to wear and damage. But from time to time in the press the sad reports of the death ships. This trouble happened on the sea many centuries ago, it is impossible to exclude completely a Maritime disaster and in the twenty-first century.
The most common cause of what is happening with vehicles accidents is the neglect of the crew to the rules of navigation. Experienced sailors know that the safest place for a ship – wise. In the sea or the ocean, the ship always lurk many troubles. Especially dangerous swimming near the coastal strip. Here are the most common strong currents, shoals and rocks that can damage the ship.
Indeed, very often the ship gets fatal damage when at full speed bumps into the obstacle. The hull skin strong enough but it has a tensile strength. If the ship got a serious hole in the hold begins to enter the water that fills the compartments. For this reason, the ship becomes unstable and may tip over.
To reduce the likelihood of flooding, the internal space of modern ships try to divide into sealed compartments within which a set of powerful pumps, able to pump out water. Worst of all, when the hole is so large that the pump cannot handle the load. A large hole in the hull to seal in the sea almost impossible. The crew's only hope for rescue funds.
Any vehicle designed so that it had a certain amount of strength and buoyancy. If the damaged ship is in the oceans under conditions of strong emotion or even a real storm, chances are that the ship will remain afloat, are reduced. In conditions of high waves, some ships have a long and narrow body, it can break in half. The result is the imminent immersion of the ship into the water.
Another reason of the sinking of the ship is placed incorrectly and carelessly secured load. During the storm the contents of the hold may well move in the direction that often leads to a strong roll. If the load on one side is critical, the ship can tip over sideways and even turn upside down, then the ship can go down.
Fully guarantee the safety of the ship through the waterways impossible. But you can reduce the possibility of tragedy, if strictly follow all the rules of operation of vessels developed by many generations of seafarers, and with the utmost attention to changing conditions, which is swimming.
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