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Homework Help: What force does the scale display in Newtons?

  1. Dec 9, 2008 #1
    Jasmine has a mass of 7 kg. He stands on a scale in an elevator that is accelerating downward at 4.9 m/sec ^2 . What force does the scale display in Newtons?


    Thank you for your help!! :]

    F = ma
    i get 34.3

    what is the unit i attach it to?
     
    Last edited: Dec 9, 2008
  2. jcsd
  3. Dec 9, 2008 #2

    tiny-tim

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    Welcome to PF!

    Hi dreamgirl! Welcome to PF! :smile:

    (please use the homework forum in future :wink:)

    Use good ol' Newton's second law … F = ma …

    what is the acceleration? and what is the force(s)?
     
  4. Dec 9, 2008 #3
    Thanks for the welcome!!! :]

    another question:
    when i get it, is the number automatically in Newtons?

    i get 34.3

    what is the unit i attach it to?
     
  5. Dec 10, 2008 #4

    tiny-tim

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    SI units

    Hi dreamgirl! :smile:

    Yes … so long as all your inputs are in SI units, the output will be in SI units also.

    The inputs are kg and m and s, so the output will be in the SI unit of force, the newton (small n, btw, like watt and joule … it's only a capital N for the symbol, like W and J :wink:).
     
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