posted by Sukie on .
A forearm with a mass of 1.2kg supports a ball with a mass of 5.44 kg. The forearm is 0.050m long; it's perpendicular to the arm is 0.35m long, the center of gravity is at 0.15m from the elbow. Find the force exerted by rhe biceps and the force on the elbow joint.
I know this is just like any other problem with center of gravity and trying to find the forces on both ends supporting the ball, but there's only one support, the elbow, so that would be the fulcrum and even then, what does the forearm length have to do with it? I don't know how to set up the equation.
can someone pretty please help?
You need to know how far from the fulcrum, the hinge at the elbow, the biceps attaches to the forearm. Move your forearm up and down. You can feel that the biceps pulls up on the forearm well forward of the pivot at the rear of the elbow. That is the distance you can not do without.
So, how can I slove it, please?