"average density"
You must combine the weight of the metal hull with that of the air contained within it.
It displaces water and is filled with air.
Metal ships are built to float.
Ships, whether made of wood or metal, have a lighter specific gravity than water. Ships actually displace the water rather than floating on it.
Needles don't float because metal is very dense and contains no air. A boat is either made of porous wood which is lighter than water, or metal with air reserves to keep it afloat.
A needle doesn't float because there is very little air in a needle. Metal is much more dense than wood, which is what most boats are made of. When a boat is made of metal, there are air stores inside of the boat that keep it afloat.
Because the volume of water it displaces weighs more than the ship. Archimedes principle says that the upwards force on the ship is equal to the weight (mass) of fluid displaced - so the ship floats
It depends. A steel ship will float just fine, so will an iron one(i.e. Old Ironsides). It all depends on the size, weight, and buoyancy of the ship.
No, for a sword is made of metal and metal is heavier than water.
Metal ships float because they are designed to displace a volume of water greater than their own weight. This displacement creates an upward force known as buoyancy, which keeps the ship afloat. Additionally, the metal used in ship construction is carefully chosen and shaped to provide the necessary strength and buoyancy.
it was a ship made of metal
You can't make a bar of metal float on water, but boats with metal hulls float. Also, metal bars and other metal objects float on mercury.
A big ship made of iron can float due to its shape and displacement. When a ship is designed with a hull that displaces enough water, it creates buoyant force greater than its weight, allowing it to float. Additionally, the weight of the iron ship is distributed over a large surface area, decreasing the pressure exerted on the water and helping it to stay afloat.