You are doing exercises on a Nautilus machine in a gym to strengthen your deltoid (shoulder) muscles. Your arms are raised vertically and can pivot around the shoulder joint, and you grasp the cable of the machine in your hand 64.0 cm from your shoulder joint. The deltoid muscle is attached to the humerus 16.0 cm from the shoulder joint and makes a 12.0? angle with that bone.
a) If you have set the tension in the cable of the machine to 33.0 N on each arm, what is the tension in each deltoid muscle if you hold your outstretched arms in place?
b) What then is the magnitude of the force on the humerus bone at the shoulder joint if you are holding your are holding your arm in place? (Assume the mass of the arm is 8.0 kg.)