1. You need to construct a hollow cubical box of aluminum that has an outside length of 20 cm and an average density of 1000 kg/m3. What must be the thickness of the aluminum sheet used to construct this box? The density of aluminum is 2700 kg/m3. Did you have to make any approximations to solve this problem?
2. A rectangular block of wood weighs 4.0 N in air and has a density of 600 kg/m3. The block is immersed in water.
a. What fraction of the volume of the block is immersed in the water?
b. A piece of iron (density 6000 kg/m3) is placed on top of the block so that 85% of the block is now immersed in the water. What is the weight of the iron placed on the block?
c. The same piece of iron is now attached to the bottom of wood that is immersed in the water. What fraction of volume of the block is now immersed in the water?