(a) F=10N 600 4 m/s 1 m B A 2 kg box is sliding across the rough horizontal surface as shown above. At point A it is moving at speed of 4 m/s. In order to reduce its speed a person applies 10 N force as shown in the diagram. The friction force on the box equals to 2N. As the box moves 1 m to point B along the surface determine, 1 . Work done by each force acting on the box Total work on the box I11. Speed at point B (after it moves 1 m) (b) A marble is projected along the smooth track shown in the diagram below with speed of 2 m/s. Determine its speed at point B A R 2 m/s 2. 6 m I m