1. A 940 kg motorboat accelerates away from a dock at 2.2 m/s2. Its propeller provides a thrust force of 3.9 kN. What is the drag force exerted by the water on the boat? 2. I know that the force can be get by F= m a 3. My teacher told us to draw a free body diagram to get all the forces acting on the object, but I'm not so sure how to do the water one.