| The figure shows a 0.41-kg block sliding from A to B along a frictionless surface. When the block reaches B, it continues to slide along the horizontal surface BC where the kinetic frictional force acts. As a result, the block slows down, coming to rest at C. The kinetic energy of the block at A is 37 J, and the heights of A and B are 12.0 and 7.0 m above the ground, respectively. Concepts: (i) Is the total me- chanical energy of the block conserved as the block goes from A to B? Why or why not? (ii) When the block reaches point B, has its kinetic energy increased, decreased, or remained the same relative to what it was at A? Give a reason for your answer. (iii) Is the total mechanical energy of the block conserved as the block goes from B to C? Justify your answer. Calculations: (a) What is the value of the kinetic energy of the block when it reaches B? (b) How much work does the kinetic *90. frictional force do during the BC segment of the trip? ha = 12.0 m B hg = 7.0 m hc = 7.0 m %3D Problem 90

| The figure shows a 0.41-kg block sliding from A to B along a frictionless surface. When the block reaches B, it continues to slide along the horizontal surface BC where the kinetic frictional force acts. As a result, the block slows down, coming to rest at C. The kinetic energy of the block at A is 37 J, and the heights of A and B are 12.0 and 7.0 m above the ground, respectively. Concepts: (i) Is the total me- chanical energy of the block conserved as the block goes from A to B? Why or why not? (ii) When the block reaches point B, has its kinetic energy increased, decreased, or remained the same relative to what it was at A? Give a reason for your answer. (iii) Is the total mechanical energy of the block conserved as the block goes from B to C? Justify your answer. Calculations: (a) What is the value of the kinetic energy of the block when it reaches B? (b) How much work does the kinetic *90. frictional force do during the BC segment of the trip? ha = 12.0 m B hg = 7.0 m hc = 7.0 m %3D Problem 90

College Physics

11th Edition

ISBN:9781305952300

Author:Raymond A. Serway, Chris Vuille

Publisher:Raymond A. Serway, Chris Vuille

Chapter1: Units, Trigonometry. And Vectors

Section: Chapter Questions

Problem 1CQ: Estimate the order of magnitude of the length, in meters, of each of the following; (a) a mouse, (b)...

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