Momentum and car design - Physics unit 2

Momentum is a property of moving objects
the greater the mass and velocity, the greater the momentum
momentum is always conserved
forces cause a change in momentum
1. when a force acts on an object, momentum changes.
2. if someone's momentum changes QUICKLY forces on the body will be large.
  1. this will cause injury
cars are designed with safety features
1. these slow people down over a longer time when they have a crash
2. the longer it takes for a change in momentum, smaller the force
the total momentum before an event is equal to the total momentum after an event
breaks do the work against the kinetic energy of a car
cars are designed to convert kinetic energy safely in a crash
when you apply breaks work is done
1. breaks reduce kinetic energy by transferring it into heat energy
in a car crash there's a large change in momentum quickly
1. this creates HUGE forces on the people inside the car
  1. injury or even death can occur because of this.
crumble zones - reduce the impact force on the person
1. kinetic energy is converted by the car.
2. increase the impact time
3. decreases the force produced by the change in momentum

Resource summary

	Created by Lucy Colman about 9 years ago