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Force Extension graph - Whats the area underneath represent ? watch

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    Okay, in the attached diagram I have labelled a region A (the area in between the two lines) and region B (the area below the lower second line.)

    Can you provide a brief explanation of what regions A and B represent ?

    I know what A represents but can seem to put it in words...
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    As its a force-extension graph, and work done is F \delta x
    then the area under a F-x graph will represent work done.
    In this case, the upper curve represents the work done on the object against tension while extending it, and the lower curve is the energy recovered (work done by the object) when the object returns to a state of no tension. The area between the curves is the difference between the two.
    Where do you think this "lost" energy has gone?
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    (Original post by Stonebridge)
    As its a force-extension graph, and work done is F \delta x
    then the area under a F-x graph will represent work done.
    In this case, the upper curve represents the work done on the object against tension while extending it, and the lower curve is the energy recovered (work done by the object) when the object returns to a state of no tension. The area between the curves is the difference between the two.
    Where do you think this "lost" energy has gone?
    Its probably been lost as heat energy, right ?

    Supposing a question asked to calculate the energy expended in causing a permanent deformation; it would area A plus area B. Correct ?
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    The "lost" energy is the result of the material having been stretched beyond its elastic limit, which is, by definition, the limit beyond which the material cannot regain its original size and shape.
    The "lost" energy has been mostly used to permanently deform the material, although some will also have been turned into heat as you correctly suggest.
    So no, not area A plus area B
 
 
 
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