Most of the motion generated by joints in the human body are examples of levers. An example of a third class lever is the forearm; the force which generates the motion is located in-between the pivot point and the resistance force. The elbow acts as the pivot point, the biceps muscle pulls up on the forearm to move the mass which is held in the hand. Imagine someone is holding an object in her hand with her forearm horizontal and her upper arm vertical so her elbow creates a 90° angle. If her biceps attach to her forearm 0.0640 m from the elbow and make an angle of 28.0° with the vertical while a 3.14 kg mass is held in her hand 28.60 cm from the elbow, what force F is exerted by the biceps muscle? Ignore the mass of the forearm.

Most of the motion generated by joints in the human body are examples of levers. An example of a third class lever is the forearm; the force which generates the motion is located in-between the pivot point and the resistance force. The elbow acts as the pivot point, the biceps muscle pulls up on the forearm to move the mass which is held in the hand. Imagine someone is holding an object in her hand with her forearm horizontal and her upper arm vertical so her elbow creates a 90° angle. If her biceps attach to her forearm 0.0640 m from the elbow and make an angle of 28.0° with the vertical while a 3.14 kg mass is held in her hand 28.60 cm from the elbow, what force F is exerted by the biceps muscle? Ignore the mass of the forearm.

Glencoe Physics: Principles and Problems, Student Edition

1st Edition

ISBN:9780078807213

Author:Paul W. Zitzewitz

Publisher:Paul W. Zitzewitz

Chapter5: Displacement And Force In Two Dimensions

Section: Chapter Questions

Problem 6STP

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