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2 Q's

  1. May 4, 2005 #1
    I need help with these.

    "Explain how a daughter can be biologicaly older then here parents"

    " Draw a diagram of all the forces at work for a 10kg robotic arm to lift a 1kg ball.

    Please Help Iv'e been staring at these questions for ever.
  2. jcsd
  3. May 4, 2005 #2

    1: I guess the question is after the twin paradox

    2: Think about it. The arm experiences the gravitiational force, the ball experiences the gravititational force and there's a force that lifts both the arm and the ball.
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