CoM reduced by total body height when bending your knee X degrees

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Pushies
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Lets say that a man with a standing height of 185cm bent his knee 30 degrees, how many centimeters will be reduced from his standing height? Assume his femur length is 60cm and his tibia (shin) length is 50cm.

Can anyone give me a hint?
I've tried to use trigonometry but i don't think i fully understand the rules of trigonometry because my answer doesn't make sense and I am afraid to show my calculations here because it looks too dumb.

Thanks in advance.
 
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Hello, and :welcome: !

PF rules require you to post an effort nonetheless; or we are not allowed to assist.
Better come up with at least a clarifying sketch before a mentor removes your thread !
Good chance you'll see the light when you make the sketch !

Oh, and: good you're not asked to say anything about the center of mass -- standing height is a lot easier :wink: !
 
How can we determine what went wrong if you don't show your calculations?

As this is a homework-like question I moved the thread to our homework section.
 
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Pushies said:
Lets say that a man with a standing height of 185cm bent his knee 30 degrees, how many centimeters will be reduced from his standing height? Assume his femur length is 60cm and his tibia (shin) length is 50cm.

Can anyone give me a hint?
I've tried to use trigonometry but i don't think i fully understand the rules of trigonometry because my answer doesn't make sense and I am afraid to show my calculations here because it looks too dumb.

Thanks in advance.
Is this question a combo of maths and biology?😂😂