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Homework Help: Force Problem with crash test car

  1. Feb 8, 2008 #1
    A set of crash tests consists of running a test car moving at a speed of 11.4 meters/sec (26 mph) into a solid wall. Strapped securely in an advanced seat belt system, a 59kg (130 lbs) dummy is found to move a distance of 0.66 meters from the moment the car touches the wall to the time the car is stopped. Calculate the size of the average force which acts on the dummy during that time.

    Where do I start?

    And how do I calculate average force?
  2. jcsd
  3. Feb 8, 2008 #2

    Shooting Star

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    You start by reading up a bit on impulse of a force.
  4. Feb 8, 2008 #3
    You are going to need to define your system first. Are you looking at the forces on the Dummy or Car. Then you have to conceptualize why is going on, which system is accellerating, and when is this occuring. Then use conservation of momentum and the relationship with impulse momentum. From there you should be able to find the force acting on the dummy.

    This is how I would approach the problem.
  5. Feb 8, 2008 #4
    well i always start out by listing what i know about the situation, and then list what i want to know. That way i have a clear mind of what im looking for, do that first and then attempt to solve it
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