Momentum

• Momentum


  A property that all moving objects have, related to their mass and velocity
• Momentum


  • A large rugby player running very fast has much more momentum than a skinny one out for a Sunday afternoon stroll
• Momentum


  Mass x Velocity
• Momentum


  • The greater the mass of an object, or the greater its velocity, the more momentum the object has
  • Momentum is a vector quantity - it has size and direction
• Calculating momentum


  p = mv
• Calculating momentum


  • A 50 kg cheetah running at 60 m/s has a momentum of 3000 kg m/s
  • A boy with a mass of 30 kg and a momentum of 75 kg m/s has a velocity of 2.5 m/s
• Conservation of momentum


  In a closed system, the total momentum before an event is the same as the total momentum after the event
• Conservation of momentum


  • In snooker, the total momentum of the balls is conserved during collisions
  • In a car crash, the momentum before is equal to the momentum after, causing a decrease in velocity
• If the momentum before an event is zero, the momentum after will also be zero (e.g. in an explosion)
• Conservation of momentum is incredibly important, make sure you get your head around it and practise it
• Calculating momentum


  Momentum (kg m/s) = Mass (kg) x Velocity (m/s)