The Energy Skate Park, built by the PhET project at the University of Colorado at Boulder, is a fun simulation that allows you to create a path for a skater and set the initial conditions for the skater’s ride – potential energy, friction, and even gravity.
Use the Energy Skate Park to create tracks that match these scenarios:
Create a simple half-pipe track where the rider rolls back and forth without leaving the track. Try the track in the Earth, Moon, and Jupiter settings. How does the rider’s behavior change? What stays the same?
Create a path with a peak in the middle. Design the track so that the peak prevents the rider from reaching the far end of the track. What is the key to achieving this goal? Using the same track, you can give your rider more energy by picking the rider up and dropping him or her onto the start of the path. Can you make the rider go over the peak? What is the key to achieving this goal? Describe why this works in terms of conservation of energy.
Create a path that will cause the rider to fall off the edge of the track. Then, adjust the friction to allow the rider to go to the edge of the path but not fall off.
Create a path that will make the rider jump from one portion of the track to another (but not fall off the edge). Set the friction to “None.” What happens to the rider’s path? Can the rider reach as high on the track as he or she started? Where does the energy go?
- Create a path with several valleys for the rider to go through without jumping. You may need to zoom out to create a path long enough for the rider to travel smoothly. Now, adjust the friction to make the rider get “stuck” in one of the central valleys.