An inventive child wants to reach an apple in a tree without climbing the tree. Sitting in a chair connected to a rope that passes over a frictionless pulley, the child pulls on the loose end of the rope with such a force that the spring scale reads 350 N. The child's true weight is 300 N, and the chair weighs 160 N. (a) Show that the acceleration of the child-chair system is upward and find its magnitude. m/s2 (b) Find the force the child exerts on the seat of the chair.

An inventive child wants to reach an apple in a tree without climbing the tree. Sitting in a chair connected to a rope that passes over a frictionless pulley, the child pulls on the loose end of the rope with such a force that the spring scale reads 350 N. The child's true weight is 300 N, and the chair weighs 160 N. (a) Show that the acceleration of the child-chair system is upward and find its magnitude. m/s2 (b) Find the force the child exerts on the seat of the chair.