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The nuchal ligament is a cord-like structure that runs along the back of the neck and supports much of the head’s weight in animals like horses and cows. The ligament is extremely stiff for small stretches, but loosens as it stretches further, thus functioning as a biological shock absorber. Figure 7.17 shows the force-distance curve for a particular nuchal ligament; the curve can be modeled approximately by the expression F(x) = 0.43x − 0.033x2 + 0.00086x3, with F in kN and x in cm. Find the energy stored in the ligament when it’s been stretched (a) 7.5 cm and (b) 15 cm.
FIGURE 7.17 Problem 42
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