Concept explainers
BIO Spiderweb An orb weaver spider with a mass of 0.26 g hangs vertically by one of its threads. The thread has a Young’s modulus of 4.7 × 109 N/m2 and a radius of 9.8 × 10−6 m. (a) What is the fractional increase in the thread’s length caused by the spider? (b) Suppose a 76-kg person hangs vertically from a nylon rope. What radius must the rope have if its fractional increase in length is to be the same as that of the spider’s thread?
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