1. The problem statement, all variables and given/known data A toy with a mass of 100g is going through a loop-the-loop with a diameter of .5m. How fast must the car be moving at the top of the loop in order to not fall. 3. The attempt at a solution At the top of the loop, there is a normal force (Fn) and the force of gravity (Fg). I'm not sure how to do this. Do I neglect one of the forces? Set one to zero, or what?