This simulation was created by Phet Interactive Simulations at the University of Colorado.

First, play with the simulation for about 5 minutes. Then, answer the questions asked.

1. (Intro Mode) Turn on the bar graph, and then put the person at the top of a ramp with two sides.
   1. What happens to his energy when he is going up the ramp?
   2. What happens to his energy when he is going down the ramp?
   3. When is he moving the fastest? Explain why by referring to his energy.
   4. When is he moving the slowest? Explain why by referring to his energy.
2. (Friction Mode) Put the skater in the same situation, but with friction. Keep the bar graph on.
   1. What is different about the skater's energy?
   2. Speaking only in terms of energy, why does the skater eventually stop moving?
   3. Trying making friction larger or smaller. What changes?
3. (Playground Mode, Friction off) Go to "playground" mode and turn friction off. Try to build a device in which the skater successfully completes a loop-de-loop (He needs to go from right side up, to upside down, to right side up, without losing contact with he track!)
   1. Draw the skate course you made.
   2. Explain how the skater's energy changes as he moves around the loop.
   3. Where on the loop is he moving slowest and why?
4. (Playground Mode: Friction on) Turn friction on. See if you can make a loop-de-loop that still works! Can you get one that works with maximum friction? If you do, draw how you did it. Explain, using energy, what makes it work successfully.
5. Which of the following loop-da-loops will work? Which will fail? Explain why by referring to the skater's energy.
   1. 
   2. 
6. Create an amazing and crazy setup. Draw it, or save a screenshot of it, and briefly explain how energy changes as the skater travels through it.