A standard man holds the upper arm vertical and the lower arm horizontal with an object of mass M = 5 kg resting on the hand, as illustrated in the figure above. The mass of the lower arm and hand is one-half the mass of the entire arm. As shown in the figure below, there are four forces acting on the lower arm: the external force Fext, exerted by the bones and ligaments at the upper arm at the elbow (fulcrum); the tension T, exerted by the biceps; a force W due to the weight of holding the holding object; and the Wf of the lower arm. The points along the lower arm at which the forces act are L1 = 5cm, L2 = 17 cm and L3 = 42 cm, as shown in the figure below. (Assume the mass of the lower arm is 2.3kg).
(a) Calculate the vertical component of the force Fext (Enter the magnitude only)
(b) Calculate the vertical component of the tension T. (Enter the magnitude only)
Please fix the following input errors:
