Edexcel A Level Physics:复习笔记4.1 Density

• Density is the mass per unit volume of an object
  • Objects made from low-density materials typically have a lower mass
  • For example, a balloon is less dense than a small bar of lead despite occupying a larger volume

   

• The units of density depend on the units used for mass and volume:
  • If the mass is measured in g and volume in cm3, then the density will be in g / cm3
  • If the mass is measured in kg and volume in m3, then the density will be in kg / m3

   

Gases are less dense than a solid

• The volume of an object may not always be given directly, but can be calculated with the appropriate equation depending on the object’s shape

Volumes of common 3D shapes