The weight of water displaced by a 100-ton ship – called displacement tonnage – is 100 tons. The type of ton used to describe displacement in ships is the long ton, which is equal to 2,240 pounds. Therefore, the weight of the water is 224,000 pounds.
Displacement tonnage is the weight of a vessel based on the volume of water displaced by its hull. Another way to describe displacement tonnage is the volume of water that must be moved to bear the weight of the ship. The buoyancy of an object determines its tendency to float on or sink in the water.