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Homework Help: Centripital Acceleration/G-Force question

  1. May 7, 2009 #1
    1. The problem statement, all variables and given/known data
    A plane is in a dive. At the bottom of the dive is the maximum acceleration on the pilot. This part of the dive can be approximated by a circular path. If the centripetal acceleration on the pilot is 7.50 times g (=9.81 m/s2), what is the force felt by the pilot if her mass is 49.0 kg.

    2. Relevant equations

    Is it this simple?


    3. The attempt at a solution

    F = (49kg)*(7.5*9.8m/s^2) = 3601.5N

    According to the online answer checker, it's not correct. I guess I'm missing something. Any ideas?
  2. jcsd
  3. May 7, 2009 #2


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    Homework Helper

    Inside the plane the pilot will experience centrifugal acceleration which is opposite to the centripetal acceleration. So the total acceleration on the pilot will be 7.5g + g.
  4. May 7, 2009 #3
    Of course! Now I feel kinda stupid. At one point in my thinking, I remember contemplating that, but for some reason it got lost. Oh well; you win some, you lose some.

    Thanks for your help.
  5. May 8, 2009 #4
    (Although as Einstein noted, the acceleration of a free object
    relative to the cockpit would indeed be 8.5g)

    Amelia Ehrhart's acceleration is 7.5g upwards.
    Gravity exerts a force mg downwards.
    Applying Newton's second Law, the force exerted on
    her backside is mg + 7.5mg straight up.
    Last edited: May 8, 2009
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