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Net Force Question?

  1. Feb 23, 2012 #1
    Question is:
    A mother weighing 58.2kg is holding onto the hand of her daughter who weighs 35.5kg. If the father grabs the hand of the mother and pulls with a force of 100N, how much net force does the daughter experience?

    Iv'e been looking through my Physics formula and can't even find anything about net force...
    would anyone by chance know a formula I could use?
  2. jcsd
  3. Feb 23, 2012 #2


    Staff: Mentor

    Net force is the sum of all forces affecting the daughter. The father is pulling horizontally I assume and so the mother pulls the daughter with same force assuming she doesn't stretch out first and then there's gravity exerting a downward force of m*g.

    So add the two forces together in a vector fashion to get the answer.
  4. Feb 23, 2012 #3
    The only force is 100N though?
    Do I add the weight of both the daughter and mother then do what with the force?
    I'm sorry for the trouble and confusion.
  5. Feb 23, 2012 #4
    figured it out.
    thanks for your help.
  6. Feb 23, 2012 #5


    Staff: Mentor

    so what answer did you get?
  7. Feb 23, 2012 #6
    37.9N downward
  8. Feb 23, 2012 #7
    well think about that for a bit, does that make sense?

    If the mom is holding the daughter and the dad yanks on the mom, what's gonna happen to the daughter?

    If what you say is true, and she experiences a net force of 37.9N downwards, then she's going to accelerate into the ground.

    Does that make sense?
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