Question: Determine the average force of friction over the first drop and over the entire trip from top to bottom. This is a question of have from a lab experment which was when we designed a "roller coaster" for a ball (it was a downwards ramps with 2 humps on it). I have the actual velocitys at all points in time that I recorded, and I calculated the theoretical speed of the ball at these 2 points by using the law of conservation of energy and calculating Ek. My question is what is this question asking? What does the "average force of friction" mean?