P10 forces and motion

• the acceleration depends on

  • the resultant force acting on the object
  • the mass of the object
• force is directly proportional to acceleration
• Newtons first law of motion (inertia)

  an object will remain at rest or constant velocity unless acted upon by an external force
• newtons II law of motion

  F=ma
• newtons III law of motion

  for every action there is an equal but opposite action
• breaking distance


  distance travelled whilst a car is breaking
• thinking distance 


  distance travelled whilst thinking about breaking
• stopping distance = thinking distance + breaking distance
• what affects thinking distance

  • distractions (phone, music, children)
  • reaction time (age, alcohol, drugs)
• what effects the breaking distance

  • condition/age of breaks
  • the weather (ice/rain)
  • the grip on tires
  • material of road/surface