Concept explainers
You’re an engineer for a company that makes bungee-jump cords, and you’re asked to develop a formula for the work involved in stretching cords to double their length. Your cords have force-distance relations described by F = − (kx + bx2 + cx3 + dx4), where k, b, c, and d are constants. (a) Given a cord with un-stretched length L0, what’s your formula? (b) Evaluate the work done in doubling the stretch of a 10-m cord with k = 420 N/m, b = −86 N/m2, c = 12 N/m3, and d = −0.50 N/m4.
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