13. (a) Isolated. The only external influence on the systemis the normal force from the slide, but this force isalways perpendicular to its displacement so it performsno work on the system. (b) No, the slide is frictionless.(c) Emgh (d) E+ zmv 2´system´system(e) Emgy max´systemxi8gh(g) ymax = h(1 - cos? 0) (h) If friction is(f) v; =V 5present, mechanical energy of the system would not be con-served, so the child's kinetic energy at all points after leav-ing the top of the waterslide would be reduced when com-pared with the frictionless case. Consequently, her launchspeed and maximum height would be reduced as well. 13. A child of mass m starts from rest and slides without fric-GP tion from a height h along a slide next to a pool (Fig. P8.13).QIC She is launched from a height h/5 into the air over the pool.We wish to find the maximum height she reaches above thewater in her projectile motion. (a) Is the child-Earth systemisolated or nonisolated? Why? (b) Is there a nonconservativeforce acting within the system? (c) Define the configurationof the system when the child is at the water level as havingzero gravitational potential energy. Express the total energyof the system when the child is at the top of the waterslide.(d) Express the total energy of the system when the child isat the launching point. (e) Express the total energy of thesystem when the child is at the highest point in her projec-tile motion. (f) From parts (c) and (d), determine her initial

a) Isolated, since there is only her weight which can do work on the child. b) No, since there is no…

A child of mass m starts from rest and slides without fric- tion from a height h along a slide next to a pool (Fig. P8.13). She is launched from a height h/5 into the air over the pool. We wish to find the maximum height she reaches above the water in her projectile motion. (a) Is the child-Earth system isolated or nonisolated? Why? (b) Is there a nonconservative force acting within the system? (c) Define the configuration of the system when the child is at the water level as having zero gravitational potential energy. Express the total energy of the system when the child is at the top of the waterslide. (d) Express the total energy of the system when the child is at the launching point. (e) Express the total energy of the system when the child is at the highest point in her projec- tile motion (f) From narts (c) and (d) determine her initial

A child of mass m starts from rest and slides without fric- tion from a height h along a slide next to a pool (Fig. P8.13). She is launched from a height h/5 into the air over the pool. We wish to find the maximum height she reaches above the water in her projectile motion. (a) Is the child-Earth system isolated or nonisolated? Why? (b) Is there a nonconservative force acting within the system? (c) Define the configuration of the system when the child is at the water level as having zero gravitational potential energy. Express the total energy of the system when the child is at the top of the waterslide. (d) Express the total energy of the system when the child is at the launching point. (e) Express the total energy of the system when the child is at the highest point in her projec- tile motion (f) From narts (c) and (d) determine her initial

Physics for Scientists and Engineers with Modern Physics

10th Edition

ISBN:9781337553292

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter8: Conservation Of Energy

Section: Chapter Questions

Problem 13P

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