09: A person trying to lose weight by burning fat lifts a mass of 10 kg up to a height of 1 m 1000 times. Assume that the potential energy lost each time he lowers the mass is dissipated. How much fat will he use up considering the work done only when the weight is lifted up? Fat supplies 3.8 X 10' J of energy per kg which is converted to mechanical energy with a 20% efficiency rate. Take g= 9.8 m/s (a) 12.89 X 10 kg (b) 2.45 X 10 kg (c) 6.45 X 10 kg (d) 9.89 X 10 kg

09: A person trying to lose weight by burning fat lifts a mass of 10 kg up to a height of 1 m 1000 times. Assume that the potential energy lost each time he lowers the mass is dissipated. How much fat will he use up considering the work done only when the weight is lifted up? Fat supplies 3.8 X 10' J of energy per kg which is converted to mechanical energy with a 20% efficiency rate. Take g= 9.8 m/s (a) 12.89 X 10 kg (b) 2.45 X 10 kg (c) 6.45 X 10 kg (d) 9.89 X 10 kg

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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2. Using data from Table, calculate the daily energy needs of a person who sleeps for 8.00 h, walks for 2.00 h, works in the office for 8 hours, does moderate physical work during 2 hours and lying awake for 4 hours. (suppose, that working in office consumes energy at the same rate as sitting upright.). Suppose that the person mass is 80-kg and his height 1.75m.
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3. During a hurricane, a large tree limb with a mass of 22-kg and a height of 13.3m falls on a roof that is 6-m above the ground. Find the potential energy of the limb before it reaches the roof.
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6. Determine the approximate work rate (in Mets) for running on a treadmill at a speed of 5.0 mph and a 4% grade elevation. What is the total caloric cost (kcal) for 190 lb man exercising for 30 minutes at this workrate?