Hooke's law for an object under tension or compression (9-3)

Question 1 of 3

Question

$\textbf{Tensile or compressive stress}$ on the object: applied force $F$ divided by the object’s cross-sectional area $A$

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Question

$\textbf{Young’s modulus}$ tells you how stiff the material is of which the object is made: Larger value means stiffer.

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Question

$\textbf{Tensile or compressive strain}$ of the object: resulting change in length divided by the object’s relaxed length

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Review

Here’s a useful way to rewrite Hooke’s law for an object under tension or compression. This will also help us define $\textit{stress}$ and $\textit{strain}$ more precisely. First we substitute $k$ from Equation 9-2 into Equation 9-1.

$F = \left(Y\frac{A}{L_0}\right)\Delta{L}$

Then we divide both sides by the cross-sectional area A: