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Any thoughts onhow to make this boat better
http://express.howstuffworks.com/express-submarine1.htm
How Submarines Sink & Swim To dive underwater and then resurface, the submarine's crew must be able to control the ship's weight or density. We can compare this to an empty can floating in the water. The empty can could become more "rock-like" and sink by pouring water into the can. By controlling the amount of water we pour into the can, we can control the rate and depth of its dive under the water's surface. Submarines have an inner and an outer steel shell, called a hull. The area in between the two hulls is called the ballast tank. It can be filled with either air or water. 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. Ballast tanks are open at the bottom. To dive, the submarine operator opens up valves at the top and lets air out. It's something like blowing bubbles when you are swimming underwater. Seawater rushes in to fill the space that was taken up by air. This changes the ship's density. When the density of the submarine is greater than the surrounding water, it begins to sink. This is called negative buoyancy. A moveable set of wings, called hydroplanes, helps control the angle of the dive. To keep the submarine at any specific depth, the crew adjusts the mixture of air and water in separate, smaller ballast tanks. The operator tries to keep the submarine's overall density about the same as the surrounding water. This is called neutral buoyancy. When the submarine reaches its cruising depth, the hydroplanes are straightened so the craft can travel level through the water. If something changes the submarine's weight and density, such as firing torpedoes, the operator must make further adjustments of the water/air mixture in the ballast tanks. "Dave Doe" wrote in message . nz... In article , says... "Dave Doe" wrote in message . nz... In article , says... "Dave Doe" wrote in message . nz... Can you sink a 'positive buoyancy' boat with water? Can you sink it with lead? You've proven my own point. What do submarines fill their ballast tanks with? positive bouyancy boat submarine - EVER. Bzzzt...Oh, I'm sorry, the correct answer is ''WATER'' . Thanks for playing. Water - ROTFL. No, subs sink cos either they're heavier than water in the first place, or they use ballast that is heavier than water such as: Lead, or for modern wartime subs I would think they'd use DU (depleted uranium). Water! - LOL. So the correct answer is most assuredly not water. Subs are made so that the mass/volume is denser than that of water - and they sink. They then have *AIR* in them that provides bouyancy - the cool thing about air is it's *compressability*. The "blow the (air) tanks" - and the decrease in bouyancy means they sink. To surface, they blow the water *out* of the air tanks, filling 'em with the air from the compressed air source. Think of a diver - FFS. They sink because of? Same as a sub - only as said, I would think modern war subs use denser material such as DU - 'cos they can afford it. So the correct answer is lead or DU. -- Duncan |
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