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## Potential and Kinetic Energy

• Potential and kinetic energy are inversely related. Potential energy is the amount of energy stored in an object based on the forces of acceleration that will act upon it. Kinetic energy could be more simply described as an object's speed, or rate of travel times its mass. When a roller coaster's cars are at the top of the highest hill, the cars simultaneously possess their greatest potential energy and least amount of kinetic energy. As the cars reach the bottom of that same hill, they possess the greatest kinetic energy and a much smaller amount of potential energy. By studying a roller coaster car's movement, students can write a report on the differences between potential and kinetic energy, and how to calculate them.

## Acceleration and Speed

• Once a roller coaster car is released from the top of the initial hill, the only force acting on its movement is gravity. The Earth's gravitational force causes downward acceleration at a rate of 32.17 feet per second per second. If students are given the height of a roller coaster's initial hill, the distance the car will travel vertically and the total weight of the cars, they will be able to calculate the speed of the car at the bottom of the hill. Students first tabulate the amount of time it takes for the car to travel the total distance, and then multiply the time of travel by the rate of acceleration. Performing these simple calculations will introduce students to the world of physics and algebra. Students can expand this experiment by dropping weighted objects from different distances, calculating how fast they will be traveling when they hit the floor, and also calculating how long it will take objects to hit the floor when dropped from different distances.

## Newton's Laws of Motion

• Newton's First Law of Motion says that an object at rest will stay at rest, and an object in motion will stay in motion unless acted upon by an outside force. A roller coaster is a well-designed example of how this law is put into practical use. Students can learn about this first law by examining a diagram of a roller coaster. Each time the roller coaster car changes direction or speed, it is acted upon by an outside force. Students can discuss in the classroom, then write a project report which identifies the forces acting on a moving roller coaster car.

## Toy Car Roller Coaster

• After learning about the forces which make roller coasters possible, students can create a roller coaster project with toy cars as a fun project to drive these lessons home. The goals of the project could include creating a roller coaster in which a car (such as a Hot Wheels toy) obtains a maximum speed or travels for the maximum amount of time. Students can even create a roller coaster in which a toy car could complete a number of loops. Students would have to apply the lessons they uncovered while studying roller coasters in order to create the roller coaster.