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Homework Help: Ball and gravitational force question

  1. Feb 9, 2008 #1
    1. The problem statement, all variables and given/known data
    Two metal balls are the same size but one weighs twice as much as the other. The balls are both released simultaneously from a height of 5.0 meters towards the ground. Which of the following must be true about the balls during the time they are falling? (Select all that apply.)

    False The lighter ball starts out moving faster than the heavier ball.

    False The heavy ball has an acceleration half as large as the lighter ball.

    False The Earth exerts a gravitational force on the heavy ball that is twice as large as that on the lighter ball.

    Ture The Earth exerts an equal gravitational force on both balls.

    True The heavy ball exerts a force on the Earth that is twice as large as the force on the Earth exerted by the lighter ball.

    Could someone please double check my answers and let me know if I got any wrong.

  2. jcsd
  3. Feb 9, 2008 #2


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    Staff Emeritus
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    You've got two of them wrong.
  4. Feb 9, 2008 #3
    Yes, I think you need to think about the difference between force and acceleration
  5. Feb 9, 2008 #4
    And maybe remind yourself of the definition of weight ...
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