Density is used to make a fair comparison between materials. Key fact Density is the mass per unit volume of a material i.e. density is the mass of 1 cm 3 or 1 m 3 of a material. The density of ...

Polar bears aren't white, strawberries aren't berries and the Earth isn't round—we'll have you rethinking everything you thought you knew! Mind-blowing facts you have to read to believe Did you know ...