Why Do Some Objects Float and Others Sink?
Have you ever wondered why a huge ship made of metal can float on the sea, but a small pebble sinks as soon as you drop it in water? The answer lies in the ideas of density and forces.
What Is Density?
Density is a measure of how much mass is packed into a certain volume (space) of a material. We can calculate density using this formula:
Something is dense if it has a lot of mass packed into a small space. For example, a metal block is usually denser than a piece of wood the same size.
Water has a density of 1 g/cm³. This means that if an object has a density greater than 1 g/cm³, it will usually sink in water. If it has a density less than 1 g/cm³, it will usually float.
