3.5 newtons laws of motion and momentum

• what is newtons first law?

  an object will remain at rest or at constant velocity unless acted upon by a resultant force
• what is newtons third law?

  when two objects interact they exert equal and opposite forces on each-other
• what is momentum? 


  p = mv
• what are the units of momentum?

  kgms^-1
• what is the principle of conservation of momentum? 


  for objects interacting in a closed system total momentum will remain the same in the specified direction unless acted upon by an external force
• what happens in an elastic collision?

  Kinetic energy is conserved

  momentum is conserved
• what happens in an inelastic collision?

  Kinetic energy is not conserved

  momentum is conserved
• what is newtons second law? 


  net force on an object is directly proportional to rate of change of momentum and acts in the same direction
• when does F=ma apply?

  for an object moving at constant acceleration
• what is impulse?


  change in momentum
• what does the area under a force time graph represent?

  impulse