Students see how potential energy (stored energy) can be converted into kinetic energy (motion). Acting as if they were engineers designing vehicles, they use rubber bands, pencils and spools to explore how elastic potential energy from twisted rubber bands can roll the spools. They brainstorm, prototype, modify, test and redesign variations to the basic spool racer design in order to meet different design criteria, ultimately facing off in a race competition. These simple-to-make devices store potential energy in twisted rubber bands and then convert the potential energy to kinetic energy upon release.

This activity shows students the engineering importance of understanding the laws of mechanical energy. More specifically, it demonstrates how potential energy can be converted to kinetic energy and back again. Given a pendulum height, students calculate and predict how fast the pendulum will swing by using the equations for potential and kinetic energy. The equations will be justified as students experimentally measure the speed of the pendulum and compare theory with reality.

Roller coasters projects are frequently used in middle and high school physics classes to illustrate the principle of conservation of mechanical energy. Potential energy transforms to kinetic energy and vice versa, with gravity being the driving force during the entire process. Even though friction force is mentioned, it is rarely considered in the velocity calculations along the coasters’ paths. In this high school lesson, the friction force is considered in the process. Using basic calculus and the work-energy theorem for non-conservative forces, the friction along a curved path is quantified, and the cart’s velocity along this path is predicted. This activity and its associated lesson are designed for AP Calculus. Practice problems/answers, a PowerPoint® presentation and student notes are provided.

In this activity, students explore how trebuchets were used during the Middle Ages to launch projectiles over or through castle walls as well as how they are used today in events such as Punkin’ Chunkin’. Students work as teams of engineers and research how to design and build their own trebuchets from scratch while following a select number of constraints. They test their trebuchets, evaluate their results through several quantitative analyses, and present their results and design process to the class.

Students learn the history of the waterwheel and common uses for water turbines today. They explore kinetic energy by creating their own experimental waterwheel from a two-liter plastic bottle. They investigate the transformations of energy involved in turning the blades of a hydro-turbine into work, and experiment with how weight affects the rotational rate of the waterwheel. Students also discuss and explore the characteristics of hydroelectric plants.

With an introduction to the ideas of energy, students discuss specific types of energy and the practical sources of energy. Hands-on activities help them identify types of energy in their surroundings and enhance their understanding of energy.

Students learn how engineers transform wind energy into electrical energy by building their own miniature wind turbines and measuring the electrical current it produces. They explore how design and position affect the electrical energy production.

Investigating a waterwheel illustrates to students the physical properties of energy. They learn that the concept of work, force acting over a distance, differs from power, which is defined as force acting over a distance over some period of time. Students create a model waterwheel and use it to calculate the amount of power produced and work done.