Normal force during a push up problem

AI Thread Summary
The discussion revolves around calculating the normal force exerted by the floor on each hand during a push-up, given a person's weight of 633 N and specific distances from the center of gravity to the hands and feet. The user is attempting to set up equations based on the lever principle, using L1 and L2 as distances from the center of gravity to the hands and feet, respectively. They express confusion over the math involved in solving the equations and seek clarification on the diagram, which represents a side view of the person in the push-up position. The user confirms that the distances refer to the hands and feet, not the left and right hands. Overall, the thread highlights the challenges of applying physics concepts to real-life scenarios in biomechanics.
Max238
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A person whose weight is W = 633 N doing push-ups.

l=====x====l==0
______ _____
0.885 0.358


Assume L1 = 0.885 m and L2 = 0.358 m. Calculate the normal force exerted by the floor on each hand, assuming that the person holds this position.

My work so far:
thinking L1 + L2 = 633
and .358Rhands=.885Rfeet; Rhands and Rfeet x and y respectivelyl

with a little substitution .358(633-x)=.885x
What I am having trouble is the simple math of solving this. I'm either doing something illogical or can't do simple math.
If this is wrong please tell me, if not what do I do? Maybe I've just been working on this problem a little too long...
 
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I don't understand the diagram. Are the two positions those of his right and left hands or those of his hands and his feet?
 
they are the hands and feet
you are seeing a sideview of the person with the x being his center of gravity
sorry
 
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