(a) Calculate the force (in N) the woman in the figure below exerts to do a push-up at constant speed, taking all data to be known to three digits. (You may need to use torque methods from later chapter.) m = 68 kg CG w Freaction 0.85 m 1.41 m N (b) How much work (in J) does she do if her center of mass rises 0.220 m? (c) What is her useful power output (in W) if she does 15 push-ups in 1 min? (Should work done lowering her body be included? See the discussion of useful work in Work, Energy, and Power in Humans.) W

(a) Calculate the force (in N) the woman in the figure below exerts to do a push-up at constant speed, taking all data to be known to three digits. (You may need to use torque methods from later chapter.) m = 68 kg CG w Freaction 0.85 m 1.41 m N (b) How much work (in J) does she do if her center of mass rises 0.220 m? (c) What is her useful power output (in W) if she does 15 push-ups in 1 min? (Should work done lowering her body be included? See the discussion of useful work in Work, Energy, and Power in Humans.) W

Principles of Physics: A Calculus-Based Text

5th Edition

ISBN:9781133104261

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter10: Rotational Motion

Section: Chapter Questions

Problem 3CQ

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