1. The problem statement, all variables and given/known data A roller-coaster car speeds down a hill pas point A and then rolls up a hill past point B. A. Car speed = 20 m/s at point A. If the track exerts a normal force on the car of 2.06x10^4N at this point, what is the mass of the car? (account for gravitational force) B. What is the maximum speed the car can have at point B for the gravitational force to hold it on the track? Diagram(I made it myself): http://gyazo.com/0415a6ba75f87f0229e08aab0f68fbe1 2. Relevant equations Circular motion Fc= (mv^2)/r Fn-mg= (mv^2)/r 3. The attempt at a solution Completely lost.