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Homework Help: Average magnitude of force during a 0.4 second impact

  1. Nov 17, 2012 #1
    1. The problem statement, all variables and given/known data

    A 40kg branch falls 5.5m and lands on a roof. The roof withstood the the impact.

    2. Relevant equations

    If the impact time was 0.4 second calculate the magnitude of the average force exerted on the roof during the impact.

    3. The attempt at a solution

    F=ma doesn't seem right because it's in free fall though.
    P=mv ≈ 415

    Is this right?
    Last edited: Nov 17, 2012
  2. jcsd
  3. Nov 18, 2012 #2


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    That is correct !
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