Pretend you are going to enter a soapbox derby. You are to build a vehicle that will roll down a long straight hill, with a total elevation drop of 100.0 meters. You build your vehicle and think it will win. The mass of the vehicle is 30.0 kilograms. What is the total mass of you and the vehicle? As the vehicle and driver hurtle down the hill, what is the maximum speed it can attain at the bottom of the hill? After several trial runs, you find that the final speed of your vehicle and driver is only 80% of that maximum speed. What are all the forces acting on the vehicle? Draw a free body diagram showing all the forces. Which force or forces contribute to the acceleration as it moves down the hill? Which force or forces reduce the acceleration?