Physics behind roller coasters

On Thursday Oct.28, students were introduced to the roller coaster project. I think that most of the students in the class, had experienced the breathtaking feeling when riding roller coasters. It is an indescribable emotion when it seems that you can fly without wings.  In order to know how to build it, is necessary to understand how the roller coaster works. Here is where physics takes the lead.

First of all, for those who don't know yet, it is important to mention that a roller coaster doesn't depend on engines in order to move. The two basic principles that are important are potential and kinetic energy. Potential energy is when the energy is stored in a object due to its position. In our case, as the roller coaster's starting point is higher, a greater force can be built in order to push the object down the hill, which will increase the speed at which the object is going down.  As the object goes down the hill the potential energy changes into kinetic energy. Kinetic energy is the energy produced by the motion. As it goes up the hill, it uses kinetic energy that will again change into potential energy at the top of the hill. For the whole motion, the rollercoaster continuously converts the energies in order to go up and down the hills. It is also important to mention about the gravitational forces that act on the roller coaster and create the thrilling feeling in our stomachs.