Concept #1: Intro to Buoyancy & Buoyant Force
Example #1: Comparing Buoyant Forces
Practice: When an object of unknown mass and volume is fully immersed in large oil (800 kg/m3 ) container and released from rest, it stays at rest. Calculate the density of this object.
Concept #2: Buoyancy / Three Common Cases
Practice: A block floats with 40% of its volume above water. When you place it on an unknown liquid, it floats with 30% of its volume above. What is the density of the unknown liquid?
Example #2: Is Crown Made of Gold? (Buoyancy)
Practice: An 8,000 cm3 block of wood is fully immersed in a deep water tank, then tied to the bottom. When the block is released and reaches equilibrium, you measure the tension on the string to be 12 N. What is the density of the wood?
Example #3: Maximum Load on Floating Board
Practice: You want to build a large storage container, with outer walls and an open top, as shown, so that you can load things into it, while it floats on fresh water, without any water getting inside. If the bottom face of the container measures 3.0 m by 8.0 m, how high should the side walls be, such that the combined mass of container and inside load is 100,000 kg?