Momentum & Collisions

Momentum & Collisions

1. P=mv

   • Momentum(kg m/s) = Mass(kg) X Velocity(m/s)

2. Momentum is a vector because it has size and direction

3. Total Momentum before collision = Total Momentum after collision

4. Forces & Momentum

   • A force acting on an object can cause a change in momentum
     • A larger change in force results in a faster change in momentum
     • A smaller change in force results in a slower change in momentum
   • Momentum in a car crash
     • In a car crash the momentum of a person changes very quickly so the force that affects them will be very large and likely to cause injury
       • So cars are now designed to slow people down over a longer period of time to reduce the force
         • Some examples of these features are:
           • Crumple zones
           • Seat belts
           • Air Bags