Concept explainers
BIO SPIDERWEB
*Based on F. Vollrath and D. Edmonds. “Consequences of electrical conductivity in an orb spider’s capture web.” Natunvissenschaften (100:12. December 2013, pp. 1163-69).
25.79 What is the best explanation for the behavior exhibited in the data? (a) Longer threads can carry more current than shorter threads do and so make better electrical conductors, (b) The thread stops being a conductor when it is stretched to 13 mm, due to breaks that occur in the thin coating, (c) As the thread is stretched, the coating thins and its resistance increases; as the thread is relaxed, the coating returns nearly to its original state, (d) The resistance of the thread increases with distance from the end of the thread.
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