A block of mass M is sliding with an initial speed vi along a horizontal surface with negligible friction. A constant force of magnitude FA is exerted on the object at an upward angle of 60o from the horizontal, causing the object to speed up. If the block remains in contact with the floor, what is the change in the block's kinetic energy as it moves a horizontal distance Δx?
½ Mvi2 + ½ FAΔx
