At what points in the model do the cars have maximum and minimum gravitational potential energy?

Explanation:

The gravitational potential energy is given by :

E = mgh

Here, mg is force acting on the car

h is height at which it is placed

It is directly proportional to the height or the position of the car. It means if the height is less then it will have minimum potential energy while if the height is more then it will have maximum potential energy.