Finding the Center of Mass of a Human Figure

AI Thread Summary
The discussion focuses on calculating the center of mass of a human figure by considering the torso, upper legs, and lower legs. The total mass of the torso, neck, and head is 42.3 kg, with its center of mass at 0.423 m above the origin. The upper legs weigh 19.8 kg, positioned at 0.190 m on the x-axis, while the lower legs and feet have a mass of 9.91 kg, located 0.492 m to the right and 0.253 m below the origin. The calculations presented aim to determine both the x and y coordinates of the overall center of mass, excluding the mass of the arms and hands for simplification. The thread seeks confirmation on the correctness of the calculations for finding these coordinates.
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Homework Statement


(1) the torso, neck, and head (total mass = 42.3 kg) with a center of mass located on the y-axis at a point 0.423 m above the origin, (2) the upper legs (mass = 19.8 kg) with a center of mass located on the x-axis at a point 0.190 m to the right of the origin, and (3) the lower legs and feet (total mass = 9.91 kg) with a center of mass located 0.492 to the right of and 0.253 m below the origin. Find the (a) x coordinate and (b) the y coordinate of the center of mass of the human figure.

Note that the mass of the arms and hands (approximately 12% of the whole-body mass) has been ignored to simplify the drawing.


The Attempt at a Solution


(42.3) (0.423)+ (19.8) (0) + (9.91) (-0.253)
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(42.3) +(19.8) + (9.91) AM I CORRECT?
 
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(a) X coordinate = (19.8)(0) + (9.91)(-0.492) / (42.3) + (19.8) + (9.91) (b) Y coordinate = (42.3)(0.423) + (9.91)(-0.253) / (42.3) + (19.8) + (9.91)
 
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