An iceberg ("ice mountain") is a block of ice that has detached from a glacier or po-lar cap in a process called calving.
An iceberg weighs several million tons and yet it floats. Recall that fresh water has a slightly lower density than ocean salt water, but the main reason is as follows.
All liquids have the property of reducing their volume when they solidify into ice. All except water. By turning into ice, water gains volume and as a result, water ice is less dense than liquid water. This is a remarkable property that explains why the Archimedes' force (also called buyant force) of a totally submerged ice cube exceeds the force of its weight, so the ice cube rises to the surface.
The flotation of an iceberg is a beautiful illustration of Archimedes' principle and this animation makes it possible to play with shapes and observe how the two forces interact. Since the density of the ice is just a little lower than that of the sur-rounding water, about 10% of the iceberg's volume emerges as buoyant force FB and weight Fg balance out.
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