To apply Newton's 2nd law, you must correctly identify all the forces without overlooking any or adding any forces that do not act directly on the object. To do so, we will draw a "free body diagram" (FBD) which represent each outside force acting on an object by a labeled arrow. The labels represent the magnitude of the force, for example, "FN" for the normal force. 2. A tennis ball of mass M is moving as shown after it has been struck by a racquet. Draw the free body diagram showing the forces acting on the ball. Assume air friction is negligible. FBD 3. A trunk of mass M is on a ramp. A rope pulls on the trunk horizontally as shown but the trunk does not move. In the box provided, draw a labeled "free body diagram" (FBD) showing all the forces acting on the trunk. All the forces in the diagram should have descriptive labels giving the name of the force, for example, "T or "F" for the tension. Do not label the weight as "g" - this is the acceleration due to gravity and is not a force. Label the weight as "F". Newton's 3rd law says that all forces come in action-reaction pair, i.e., if object A exerts a force on B, object B must exert the same force on A but in the opposite direction. Note that action-reaction pairs always must be the same type of force. a. What is the reaction force corresponding to the ramp pushing into the trunk? What type of force is it? What direction is the reaction force and what object does the reaction force act on? b. What is the reaction force (type, direction, and object) corresponding to the rope pulling the trunk to the right? Give type of force, the direction of the reaction force, and what object the reaction force acts on. C. What is the reaction force corresponding to the Earth pulling down on the trunk? FBD d. What is the reaction force corresponding to the force that prevents the trunk from sliding? e. The purpose of drawing the free body diagram is to use it when we write out Newton's 2nd law. Why are the reaction forces not included in the free body diagram for the trunk?