1. The problem statement, all variables and given/known data A race car travels at a constant speed on a circular track. The net force on the car is 1600N. What kind of force creates the acceleration? a) air resistance b) friction tangent to the circle c) friction toward the center of the circle d) friction away from the center of the circle e) force of the engine 2. Relevant equations Concepts of centripetal acceleration and force. 3. The attempt at a solution I know that it is not a; however, I am not sure what way the friction is directed or if the answer is e. My main guess would be toward the center of the circle, since that is the direction of the acceleration, but I'm not sure.