Why doesn't a supertanker sink?
439796
Oil has less density than water so it floats.  When it's empty, air has less density than water.  Same thing.  Or it has to do with the displacement as mentioned below...
699868
To sink down, it makes the density become more than the sdea water. It's done by filling the tanks with water, with pressure, making the temp lower. (At constant  volume, if the temperature is invertly proportional to the pressure). i.e increase in pressure at const volume, with decresing temperature increases the density. \n\nThe quite opp makes the submarine float up.
795902
no.\n\nit's a matter of physics. the hole was alreay made and filling. nothing could have been done to make the boat float longer.
291004
if an object is floating, the buoyant force on it equals its weight -- the vertical forces have to sum to zero.  try drawing a free body diagram to convince yourself of this.
1047703
Fish don't hold thier breath
904693
If you've got a submarine shaped like a flat-nosed bullet and accelerate it to supercavitation speed, a few hundred km/hour, the water in front of it will be pushed sideways and the sub will be surrounded by a bubble containing nothing but a little water vapour at low pressure.   The only part of the sub in contact with the water would be the flat nose tip.  If you could make it work, you'd cross the Atlantic at airliner speed.  Problems that spring to mind are the huge amount of energy you'd need, how you'd see far enough ahead to avoid an obstacle like a whale, and the effect on marine life.  A possible fuel would be aluminium powder, which you'd react with the water.
190543
That depends upon the location of the air and the mass of the balloon compared to its volume.\n\nAt extreme altitudes the air is less dense than the helium (if it is at room temperature) and a helium filled balloon will sink.  This is also true if the mass of the balloon plus the mass of the helium is more than the buoyancy provided by the volume of the balloon.\n\nUnder “normal” circumstances, with a typical latex or Mylar balloon filled with helium, the difference between the mass of the helium in the volume of the balloon and a similar volume of air (which is denser) is what provides the “lift.”  This is the same reason that most wood floats on water.
905607
make a little "boat" that you can add weights to and float it in the different liquids.  Gradually add weight to the boat in each liquid to see how much it can hold before it sinks.  The more weight the boat can hold, the greater the density of the liquid!\n\nThis is basically a poor-man's hydrometer.
1005012
Maybe it has something to do with grounding. If a ship is in the ocean and not touch anything then there is no reason for the current to go up right?
594942
It is said that the SHIP sinks in the water in that area.\nThat's may be due to higher gravity or some other force which is still unknown.
429114
coz the principle of bouyancy comes into action. that is there is a space with air in the bottom part of the ship/boat n hence it doesnt allow it to sink.. n that too that a greater surface area is there so the pressure is distributed over a larger area. \n u can also call it Upthrust.\nexplanation-\nArchimedes discovered the law of bouyancy. It states: on everybody emersed in water (or fluid in general) there acts an upward force with magnitude equal to the wieght of displaced water/fluid.\n\nthere are 3 scenarios for a body in water:\n\n1. floats on the surface; gravity of the body equals bouyancy and equals exactly the amount of weight of the displaced water\n\n2. the body is entirely emersed in water; again gravity = bouyancy\n\n3. the body sank; gravity = boyancy + normal reaction of the floor.
64876
Buoyancy is simple.  If the weight of the liquid moved by insertion of an object into the liquid is greater than the weight of the object, it will float.  That is why the size of ships are measured in displacement.  The "Displacement" refers to the weight of water that is "moved out of the way".\n\nThink of it this way - take two identical spheres with the exact same outer material and thinkness.  One is hallow, and one is filled with lead.  Of course, we know that the one filled with lead will sink?  Why?  Because it weighs more than the water that is being moved out of the way.  How do you make it neutrally bouyant?  Simply fill it with enough lead that equals the weight of the water displaced by the sphere.\n\nThis is called Archimedes Law of Bouyancy.  Google/Yahoo search it and you should find some illustrations to help explain.
7965
As a former submariner let me take a stab at this one...\n  Structurally the sub would fare fine in space as the pressure hull is designed to enclose a pressurized and self-contained environment for humanbeings.  The ship would not be ripped apart, easily as earlier suggested, or at all.  The flexible steel (HY 100 is the designation) is designed to flex under exerted compressing force, but that has little relevance to the discussion.  think about it this way, the space shuttle would not be a survivable vehicle under the sea due to its construction, however it is also no "ripped" apart in space.  To follow in that vein, human beings operating in the near-vacum of space are also not ripped apart, but tend to drift away from objects if not strapped to them.  Now that we have established that the submarine would be well suited to survive in space let's deal with some other issues.\n  The key problem with a submarine crew survivng in space would be where the air would come from.  Submariners breath air that is derived from one of two place, the outside atmosphere or through the process of electrolysis whereby H2O is brought into the ship and split into basic hydrogen and oxygen atoms.  The oxygen is circulated through the boat and the hydrogen is released through a diffuser back into the water.  In the case of an emergency apparati called "oxygen candles" are used to produce limited amounts of oxygen while the crew either repairs the problem or awaits rescue.  \n  So, to sum up, the submarine itself would be fine in space, assuming you could engineer enough boost to get it there and figure out a way for it to provide a means of propulsion (the propeller/screw is clearly going to be useless) for itself.  The submarine crew would be faced with how to breath given that the native atmosphere creation equipment isn't suited to a near-zero oxygen environment.  Other than those minor issues, where do I sign up?
637566
It looked like the hover boards worked with some sort of magnet on the bottom that probably conteracted with the earth's magnetic force. Since, water isn't magnetic, the hoverboard wouldn't work on water. Thats what I thought at least.
1055798
The problem is the transport of water to the top. Depending on the species, the power of the capillaries is limited (perhaps the wrong word, I'm not so common with biology in English).
1024075
perhaps u dont eat enough fiber, so your intestines arent as able to compact your feces as tightly, resulting in less dense feces which float in water. Eat more fiber, and u should have the brown submarines in the toilet bowl. lol
1063906
You're confusing resistance with pressure. If indeed there is a difference in voltage between A and B then there will be flow.\nThink of a tank filled with water held a few feet above another tank that has a pipe joining the two. Water will flow to the lower container thru the pipe. In this case the pipe has no resistance, which means water flows at maximum possible speed.\nIf both tanks are at the same level, then, sure, there will be no water flow. That's not how the problem was stated, however.