Define density. How is it related to floating and sinking in water?
Density of a substance is its mass per unit volume. It varies with temperature and pressure.
It is related to sinking and floating in water. If a substance is denser than water it will sink in water and settles down at bottom. If a substance floats on water it is less denser than water. For example, oil droplets floats on water surface while sand particles settle down at bottom.
DENSITY is a physical property of matter, as each element and compound has a unique density associated with it. Density defined in a qualitative manner as the measure of the relative "heaviness" of objects with a constant volume.
For example: A rock is obviously more dense than a crumpled piece of paper of the same size. A styrofoam cup is less dense than a ceramic cup.