1. a) A boy pulls a wagon 30m along a sidewalk with a rope tension force of 80N.The force is directed 25° above the horizontal. How much work is done by the boy? b) How much work is done if the same tension force is directed parallel to the ground? 2. A 5kg rabbit and a 12kg Irish setter have the same kinetic energy. If the setter is running at a speed of 4m/sec, how fast is the rabbit running? 3. A large tree can evaporate 500kg of water a day. a. If the water is raised 8m, how much energy must be provided by the tree to lift the water this distance? b. If the evaporation occurs over 12 hr. period, what is the average power in watts needed to provide this increase in gravitational energy?

1. a) A boy pulls a wagon 30m along a sidewalk with a rope tension force of 80N.The force is directed 25° above the horizontal. How much work is done by the boy? b) How much work is done if the same tension force is directed parallel to the ground? 2. A 5kg rabbit and a 12kg Irish setter have the same kinetic energy. If the setter is running at a speed of 4m/sec, how fast is the rabbit running? 3. A large tree can evaporate 500kg of water a day. a. If the water is raised 8m, how much energy must be provided by the tree to lift the water this distance? b. If the evaporation occurs over 12 hr. period, what is the average power in watts needed to provide this increase in gravitational energy?

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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