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Homework Help: Scales stacked together: reading on each?

  1. Jul 22, 2008 #1
    1. The problem statement, all variables and given/known data

    A standard scale (shown below) has an internal spring and a dial which shows the force exerted on the pan by this spring. The instrument has a mass of about 1 kg and weight 10 N. Ignore the weight of the light pan. To conserve space, the new metric commissioner stacks a pair of those scales as shown, one upside down on the other. We see them from the back, but what should the dials be showing (in Newtons)? Explain.


    3. The attempt at a solution

    from what i understand, they should both show 10 N. the weight of the top scale causes the bottom one to read 10 N, and the normal force pushes back up on the top scale with 10 N. is this correct?
  2. jcsd
  3. Jul 22, 2008 #2

    Doc Al

    User Avatar

    Staff: Mentor

    Sounds good to me.
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