posted by Narayanan .
A block of mass 200g and density 0.8g/cm3 is submerged in a liquid of density 0.2g/cm3. find minimum force required to keep the block floating.
The volume of the mass is
V = 200/0.8 = 250 cm^3 = 250*10^-6 m^3 and the buoyancy force (up) is
Fb = V*200 kg/m^2*g = 0.49 N.
The weight force (down) is 0.2 kg*g = 1.96 N.
To keep it floating, an upward force of at least 1.96 - 0.49 N = 1.47 N is needed
3) Calculate the mass of a substance that has a density of 0.788 g/cm3 and occupies a volume of 800 cm3.