As we have learned in this unit, Hooke’s law cannot perfectly predict the relationship between stress and strain of materials. See Figure 10.32 on p. 279 in the textbook. Can you provide your opinion why the materials behave like this on the elastic limit? Do you think we need new physics to explain that? Share your idea with other students.
Please include the name of the person or question to which you are replying in the subject line. For example, “Tom’s response to Susan’s comment.” If you agree or disagree on the subject that youre replying to, please show your own opinion clearly based on your own experience/thought why you agree/disagree.
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MARY ELLEN:
Hooke’s law does not perfectly predict the relationship between stress and strain of the materials.  I have seen this first hand.  I enjoy making rosaries and I often repair pieces for friends.  The most common breakage I see is when eyepins that are holding beads together breakdown if the piece is used and handled often.  it is the stress and strain of the bending of the metal that causes it to break down.  You can bend metal and straighten it again but eventually it becomes weak and will break, a new piece must be provided in its place. My opinion as to why this happens is that the molecules are distorted by the friction of the movement.  It would be interesting to have the ability to make something indestructible as someone else already posted.