A 53.2-kg skateboarder starts out with a speed of 2.33 m/s. He does 85.8 J of work on himself by push with his feet against the ground. In addition, friction does -296 J of work on him. In both cases, the forc doing the work are non-conservative. The final speed of the skateboarder is 8.68 m/s. (a) Calculate the change (PE-PEo) in the gravitational potential energy. (b) How much has the vertical height of the ska- changed? Give the absolute value.

A 53.2-kg skateboarder starts out with a speed of 2.33 m/s. He does 85.8 J of work on himself by push with his feet against the ground. In addition, friction does -296 J of work on him. In both cases, the forc doing the work are non-conservative. The final speed of the skateboarder is 8.68 m/s. (a) Calculate the change (PE-PEo) in the gravitational potential energy. (b) How much has the vertical height of the ska- changed? Give the absolute value.

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Description: A 53.2-kg skateboarder starts out with a speed of 2.33 m/s. He does 85.8 J of work on himself by pushwith his feet against the ground. In addition, friction does -296 J of work on him. In both cases, the forcdoing the work are non-conservative. The

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 100CP: The surface of the preceding problem is modified so that the coefficient of kinetic friction is...

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