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 why does an iron nail sink but an iron ship float?
Asked by tejalbhasker(student) , on 28/6/11

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Hi Tejal,
Iron nail does not displaces water enough and hence the buoyant force is not enough to prevent it from sinks.
It is a well known fact that an object floats on water if it displaces water equal to its own weight. The more water the ship displaces the more buoyant or floatable it becomes.
A ship sinks into the water until it has displaced is equal to its own weight of water. A ship is shaped to displace its own weight of water before it reaches the point where it will submerge.
This is in accordance with Archimedes’ principle of buoyancy which states that when a body is immersed wholly or partially in a liquid, it experiences an upward buoyant force of magnitude equal to the weight of the liquid displaced by it.

Hope, it is clear as why a ship float in water and iron nail sinks does.
Good luck.

Posted by roopeshmicasaon 6/7/11

This conversation is already closed by Expert

More Answers

when volume increases density decreases . when volume decreases density increases .the volume of the iron nail is less and thus its density is more than that of water .hence it sinks in water.the volume of an iron ship is more and of course the density is less . that is why it floats on water.

Posted by mhva09...(student)on 1/7/11

A ship floats because it is hollow from inside and that desreases its mass wich thereforedecreases its density. a nail sinks because compared to its volume its mass is great. thats why nail sinks and aship doesnt

Posted by Anvay Srivastav...(student)on 18/7/11

  1.  because the density of sea water is more than the density of the ship 
  2. the sea water contains salt in it and salt helps to float in water .

Posted by ashakeshopur...(student)on 27/7/11

 The iron nail does not have air in it, and the ship has hollowed surface in it and contains air in it.

Posted by Suryansh Chauha...(student)on 12/8/11

 the ship has hollowed surface in it and contains air in it and hense it besomes less dense than water.d=m/v.

Posted by abhijitanilm...(student)on 24/11/11

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