What is Density?

Density tells us how tightly packed the matter in an object is. Formula: Density = Mass / Volume.

Think about a block of wood and a block of iron of the same size. The iron feels much heavier, right? That is because iron is more dense—it has more mass packed into the same amount of space compared to the wood. This is why a small stone sinks in water (higher density than water) while a giant log of wood floats (lower density than water).