Question

Does the density of a block of wood and ice have to be less than the density of water in order to float (i.e. not be completely submerged)? Explain.

Please have clear hand writing.

Answer 1

Yes, the density of a block of wood and ice have to be less than the density of water in order to float because if the density of a block of wood or ice is less than the density of water, then the volume of water replaced by the block will be less than the volume of the block as the block will replace the water of same mass.

Mass of water replaced = mass of the block
If the density of block < density of water
then, the volume of water replaced < the volume of the block (density=mass/volume)
Therefore some part of the block will not be submerged.