Notice that we only have to work with vertical components, __Fn = ma (normal force Manuel exerts on box) (upward direction) __Fw = mg (weight of box) (downward direction) Because there is no change in motion, the sum of the vertical components should be equal to 0 or balance each other out. Therefore, ΣFy = Fn + (-Fw) 0 = Fn + (-mg) [solve for Fn] mg = Fn (5kg)(9.8m/s²) = 49 N = Fn = Force that Manuel is exerting on box (upward direction)
