A woman is holding an 8-lb weight in her hand with the entire arm held horizontally as shown in the fig- ure. A tensile force in the deltoid muscle prevents the arm from rotating about the shoulder joint O; this force acts at the 21 angle shown. Determine the force exerted by the deltoid muscle on the upper arm at A and the x- and y-components of the force reac- tion at the shoulder joint O. The weight of the upper arm is Wy = 4.1 lb, the weight of the lower arm is W, = 2.4 lb, and the weight of the hand is WH = 0.9 lb; all these weights act at the locations shown in the figure. 8 lb Deltoid muscle FD 21 %3D W. WH -5.2 16.5" 25.4"

A woman is holding an 8-lb weight in her hand with the entire arm held horizontally as shown in the fig- ure. A tensile force in the deltoid muscle prevents the arm from rotating about the shoulder joint O; this force acts at the 21 angle shown. Determine the force exerted by the deltoid muscle on the upper arm at A and the x- and y-components of the force reac- tion at the shoulder joint O. The weight of the upper arm is Wy = 4.1 lb, the weight of the lower arm is W, = 2.4 lb, and the weight of the hand is WH = 0.9 lb; all these weights act at the locations shown in the figure. 8 lb Deltoid muscle FD 21 %3D W. WH -5.2 16.5" 25.4"

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter4: Coplanar Equilibrium Analysis

Section: Chapter Questions

Problem 4.41P: The center of gravity of the 3000-lb car is at G. The car is parked on an incline with the parking...

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