(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 a later chapter.) m = 65 kg CG w Freaction 0.89 m 1.49 m (b) How much work (in J) does she do if her center of mass rises 0.260 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 a later chapter.) m = 65 kg CG w Freaction 0.89 m 1.49 m (b) How much work (in J) does she do if her center of mass rises 0.260 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

University Physics Volume 1

18th Edition

ISBN:9781938168277

Author:William Moebs, Samuel J. Ling, Jeff Sanny

Publisher:William Moebs, Samuel J. Ling, Jeff Sanny

Chapter11: Angular Momentum

Section: Chapter Questions

Problem 49P: The blades of a wind turbine are 30 m in length and rotate at a maximum rotation rate of 20 rev/min....

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