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Homework Help: Which one of these 3 graphs represents Hooke's law?

  1. Dec 18, 2012 #1
    1. The problem statement, all variables and given/known data
    Which one obeys Hooke’s Law and why?

    For the material(s) that did obey Hooke’s Law, calculate the spring constant, k. SHOW ALL WORK: listed variables, units, equations without substitutions, equations with substitutions, final answer with units!

    The Green line on the graph represents the Rubberband, Blue and Red represent Spring 1 and 2 respectively.

    2. Relevant equations
    F=-k(x)


    3. The attempt at a solution

    From what I can tell, Hooke's law has a linear relationship, so the line would be perfectly straight. Spring 2 is almost the same as its perfect fit line, so I think it does follow the law (it's a little different due to human errors, I am thinking). Does any other graph represent Hooke's Law? They seem to deviate from their perfect fit line a lot more than spring 2. Also, to calculate the spring constant, would I have to use F=-k(x) for each of the points I gathered than find the average (I have a force/weight and displacement table as well)? The slope of the line shown is for the perfect fit so I am not sure. Thank you for your time!
     

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  3. Dec 19, 2012 #2

    mfb

    User Avatar
    2017 Award

    Staff: Mentor

    Right.
    Right
    The fitted value from excel is better.
     
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