Kate, a bungee jumper, wants to jump off the edge of a bridge that spans a river below. Kate has a mass m, and the surface of the bridge is a heighth above the water. The bungee cord, which has length I when unstretched, will first straighten and then stretch as Kate falls. Assume the following: • The bungee cord behaves as an ideal spring once it begins to stretch, with spring constant k • Kate doesn't actually jump but simply steps off the edge of the bridge and falls straight downward. • Kate's height is negligible compared to the length of the bungee cord. Hence, she can be treated as a point particle. Use g for the magnitude of the acceleration due to gravity. ▼ Part A How far below the bridge will Kate eventually be hanging, once she stops oscillating and comes finally to rest? Assume that she doesn't touch the water. Express the distance terms of quantities given in the problem introduction. ▸ View Available Hint(s) d= Submit —| ΑΣΦ C

Kate, a bungee jumper, wants to jump off the edge of a bridge that spans a river below. Kate has a mass m, and the surface of the bridge is a heighth above the water. The bungee cord, which has length I when unstretched, will first straighten and then stretch as Kate falls. Assume the following: • The bungee cord behaves as an ideal spring once it begins to stretch, with spring constant k • Kate doesn't actually jump but simply steps off the edge of the bridge and falls straight downward. • Kate's height is negligible compared to the length of the bungee cord. Hence, she can be treated as a point particle. Use g for the magnitude of the acceleration due to gravity. ▼ Part A How far below the bridge will Kate eventually be hanging, once she stops oscillating and comes finally to rest? Assume that she doesn't touch the water. Express the distance terms of quantities given in the problem introduction. ▸ View Available Hint(s) d= Submit —| ΑΣΦ C

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter7: Work And Kinetic Energy

Section: Chapter Questions

Problem 39P: A bungee cord is essentially a very long rubber band that can stretch up to four times its...

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A bungee cord is essentially a very long rubber band that can stretch up to four times its unstretched length. However, its spring constant vanes over its stretch [see Menz, P.G. “The Physics of Bungee Jumping.” The Physics Teacher (November 1993) 31: 483-487]. Take the length of the cord to be along the direction and define the stretch as the length of the cord minus its un-stretched length that is, (see below). Suppose a particular bungee cord has a spring constant, for of and for. (Recall that the of (Recall that the spring constant is the slope of the force versus its stretch (a) What is the tension in the cord when the stretch is 16.7 m (the maximum desired for a given jump)? (b) How much work must be done against the elastic force of the bungee cord to stretch It 16.7 m? Figure 7.16 (credit modification of work by Graeme Churchard)
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