Newton’s Second Law Newton’s Second Law


  1. Newton’s Second Law:
  2. The acceleration of an object is proportional to the resultant force acting on the object, and inversely proportional to the mass of the object.
  3. As an equation:
  4. resultant force = mass × acceleration
  5. F = ma
  6. force, F, in newtons, N
  7. mass, m, in kilograms, kg
  8. acceleration, a, in metres per second squared, m/s2(HT only) Students should be able to explain that:
    • inertial mass is a measure of how difficult it is to change the velocity of an object
    • inertial mass is defined as the ratio of force over acceleration.
    • Students should be able to estimate the speed, accelerations and forces involved in large accelerations for everyday road transport.
    • Students should recognise and be able to use the symbol that indicates an approximate value or approximate answer,

WS 4.2 Recognise the importance of scientific quantities and understand how they are determined.







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