Calculating the Center of Mass of a Leg

AI Thread Summary
To calculate the center of mass of a leg, one must consider the leg's position when stretched out and bent at 90 degrees, assuming a total height of 1.70 m. The challenge arises from determining the mass distribution of different leg segments, as the problem does not provide specific mass values or diagrams. It is suggested that standard models from kinesiology may offer insights into the mass distribution of limb sections. The height given may not directly correlate to leg length, leading to confusion about its relevance. Overall, the lack of detailed information makes the calculation complex and requires external resources for accurate modeling.
hawkeye1029
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Homework Statement


Determine the position of the center of mass of a whole leg (a) when stretched out, and (b) when bent at 90°. Assume the person is 1.70 m tall.

Homework Equations


cm_def_big.gif


The Attempt at a Solution


This is where I'm stuck...what's the mass? I doubt I can just use variable m because the mass is different parts of the leg. Also, when the problem says that the person is 1.7 m tall, should I use that for leg length and assume they meant leg length instead of height?
 
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Is that all the information you are given? No diagram or anything? I think I would be led to believe that the point about the person being "1.70m tall" is some sort of red herring.
 
Yes, sadly that's all the information I'm given, not even a diagram.
 
There's probably some standard body part model used in kinesiology and the like. No doubt there are mass models for sections of each limb, and I wouldn't be surprised if there's some sort of height index to scale the model.

Where does this problem come from?
 
It's from my physics homework :cry:.
 
I would guess that your professor assigned you this piece of work but forgot to reference where you could find the question in your textbook, maybe you'll find more information there :oldtongue:
 
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