To determine the center of mass of her body, a student lies on a plank of mass m=10 kg.The plank is supported by two scales at its ends. The distance between the scales is 2.5 meters. The left scale reads 339 N and the right scale reads 171 N.
a) Draw on the picture above all of the forces acting on the plank. Pay attention to their directions.
b) Find the weight of the person in Newtons.
c) The distance from the student's head to her center of mass.