A semi-cylindrical groove of radius r = 20 cm is made on a horizontal floor. An ant wants to cross the groove. A boy decides to help the ant making a bridge consisting of straight wire segments. But all the wires available are of length l = 38 cm, so the boy rigidly connects two wires at right angle and places the bridge in the groove as shown in the figure. If the ant can crawl up a wire segment at speed v = 0.5 cm/s and down a wire segment at speed 2v, in what minimum time can the ant cross the groove with the help of this bridge?

A semi-cylindrical groove of radius r = 20 cm is made on a horizontal floor. An ant wants to cross the groove. A boy decides to help the ant making a bridge consisting of straight wire segments. But all the wires available are of length l = 38 cm, so the boy rigidly connects two wires at right angle and places the bridge in the groove as shown in the figure. If the ant can crawl up a wire segment at speed v = 0.5 cm/s and down a wire segment at speed 2v, in what minimum time can the ant cross the groove with the help of this bridge?

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter9: Energy In Nonisolated Systems

Section: Chapter Questions

Problem 16PQ

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