In the figure, a 11 kg block is held in place via a pulley system. The person's upper arm is vertical; the forearm makes angle 0 = 30° with the horizontal. Forearm and hand together have a mass of 1.8 kg, with a center of mass at distance d1 = 14 cm from the contact point of the forearm bone and the upper- arm bone (humerus). The triceps muscle pulls vertically upward on the forearm at distance d2 = 2.5 cm behind that contact point. Distance d3 is 40 cm. Take the upward direction to be positive. What are the forces on the forearm from (a) the triceps muscle and (b) the humerus? %3D

In the figure, a 11 kg block is held in place via a pulley system. The person's upper arm is vertical; the forearm makes angle 0 = 30° with the horizontal. Forearm and hand together have a mass of 1.8 kg, with a center of mass at distance d1 = 14 cm from the contact point of the forearm bone and the upper- arm bone (humerus). The triceps muscle pulls vertically upward on the forearm at distance d2 = 2.5 cm behind that contact point. Distance d3 is 40 cm. Take the upward direction to be positive. What are the forces on the forearm from (a) the triceps muscle and (b) the humerus? %3D

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter9: Statics And Torque

Section: Chapter Questions

Problem 17PE: To get up on the roof, a person (mass 70.0 kg) places a 6.00-m aluminum ladder (mass 10.0 kg)...

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