A woman of mass m = 53.4 kg sits on the left end of aseesaw—a plank of length L = 4.25 m—pivoted in the middleas shown in the figure.
(a) First compute the torques on the seesawabout an axis that passes through the pivot point. Where should aman of mass M = 67.7 kg sit if the system (seesaw plus manand woman) is to be balanced?
(b) Find the normal force exerted by the pivot ifthe plank has a mass of mpl = 12.8 kg.
(c) Repeat part (a), but thistime compute the torques about an axis through the left end of theplank (m).
EXERCISE
Suppose a 32.0 kg child sits 1.87 m to the left of center on thesame seesaw as the problem you just solved. A second child sits atthe end on the opposite side, and the system is balanced.
(a) Find the mass of the second child(kg).
mchild 2 =
(b) Find the normal force acting at the pivotpoint (N).
Fn = Â Â
