A mother leans horizontally over the crib to lift her 18.8 kg baby. The moment arm of the baby about the hip joint is b = 0.54 m. Her upper body has a mass of 57.0 kg and a moment arm of t= 0.390 m. The back muscles are equivalent to a single muscle with an angle theta = 12.0° to the horizontal spine giving a moment arm of r = 0.081 m. Calculate the tension in her backbone when she lifts her child. For your own education convert this load into pound weight to appreciate the magnitude of the load on the back muscles and spine. This explains why you should keep the spine upright when lifting. Tv

A mother leans horizontally over the crib to lift her 18.8 kg baby. The moment arm of the baby about the hip joint is b = 0.54 m. Her upper body has a mass of 57.0 kg and a moment arm of t= 0.390 m. The back muscles are equivalent to a single muscle with an angle theta = 12.0° to the horizontal spine giving a moment arm of r = 0.081 m. Calculate the tension in her backbone when she lifts her child. For your own education convert this load into pound weight to appreciate the magnitude of the load on the back muscles and spine. This explains why you should keep the spine upright when lifting. Tv

Glencoe Physics: Principles and Problems, Student Edition

1st Edition

ISBN:9780078807213

Author:Paul W. Zitzewitz

Publisher:Paul W. Zitzewitz

Chapter8: Rotational Motion

Section: Chapter Questions

Problem 1STP

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