What Is the Vertical Force at the Elbow Joint?

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annanause
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Homework Statement


State an expression for the vertical force at the elbow joint FE in terms of the other forces acting when the arm is held horizontal with the dumbbell in the hand.
Free-body diagram of a horizontal arm holding a 1.5 kg dumb-bell: upward force FB at muscle M, downward force FE at elbow joint E, weight W of the dumb-bell at D, and a 25 N force; distances 6.8 cm, 19.0 cm and 37.0 cm marked.


Homework Equations


No equations needed.

The Attempt at a Solution


Since muscles can not expand beyond their resting length, joints and muscles often exert forces that act in opposite directions and thus subtract.

Am I even close to what I was asked to answer?
 
annanause said:
Am I even close to what I was asked to answer?
No, the question is asking for an equation relating the forces. It's not entirely clear, but I think it just wants one relating to the sum of the vertical forces; looks like moments get considered later in the question.