Mass & Inertia

Physics: AQA GCSE Higher, topic 5.2.1

Mass

The mass of an object is a measure of the amount of matter it contains. The mass of an object is constant. It is the same on Earth, on the Moon and in space.

Amount of matter

Amount of matter

  • An object's mass is a measure of the amount of matter that it contains.
Inertia

Inertia

  • An object's mass is also a measure of how difficult it is to change the object's motion.
  • This is called inertia.
  • An object with a high mass has more inertia than an object with a lower mass.
  • It is difficult to move an object with a high mass (and high inertia), and once it is moving, the object’s motion is hard to stop.

Test yourself on Mass & Inertia

  • Which of the following are true of mass and inertia?

  • Which of these is the correct definition of inertia?

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