A large arm model was constructed with a free arm which weights 1 kg and has a center of gravity 12 cm from the pivot.
a. if the force cord is attached 1 cm from the pivot, what force must be applied to support the free arm at 90 degrees?
b. an additional weight of 1 kg is supported by the arm at a distance of 12 cm from the pivot. What is the total torque of the resistance? What effort force will be required to support the arm and weight?