Page 24 - York Global Science 6 - Physical Science

To compare the density of different materials, you need to look at the mass and
the volume of the objects.

If two objects have the same volume, the object that has the highest mass is
more dense because it has a larger number of particles.

house brick 225 g polystyrene 25 g

If two objects have the same mass, the object that has the smallest volume is
more dense because the particles are packed into a smaller space.

500 g 500 g

Let’s Understand

Different solids and liquids have different densities.

A piece of iron is more dense than a piece
of aluminium of the same size. This is
because the iron atoms are packed more
closely together and iron atoms have

more mass than aluminium atoms.
Water has a density of 1 g/cm .
3
• An object that has a higher density than
water will sink.

• An object that has a lower density than water will float.

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