The average density of icebergs is about 917 kg/m3. (a) Determine the percentage of the total volume of an iceberg submerged in seawater of density 1042 kg/m3. (b) Although icebergs are mostly submerged, they are observed to turn over. Explain how this can happen. (Hint: Consider the temperatures of icebergs and seawater.)
Consider an iceberg floating in seawater as shown in the fig below.
The volume fraction of the iceberg submerged in seawater can be determined as follows.
The weight of a body floating(iceberg) in a fluid is equal to the buoyant force acting on it . Therefore,
The densities of iceberg and seawater are 917 kg/ and 1042 kg/respectively.
= = = 0.88 = 88%
The percentage of the total volume of an iceberg submerged in seawater of density 1042 kg/is 88%
Transfer of heat to the iceberg from seawater due to the temperature difference between the
seawater and an ice berg causes uneven melting of the irregularly shaped iceberg.
The resulting shift in the center of mass causes the iceberg to turn over.