NAME_____________________________________PERIOD_________DATE Energy of a Pendulum PHET activity 1. Find the Pendulum Lab on the PHET website. (phet.colorado.edu, and search for Pendulum Lab simulation) 2. Download the simulation and run it off the computer (it’s faster that way). 3. Leave settings as they are, or click on RESET, and then click on the button “Show Energy of: 1” and make sure friction is set to NONE and gravity is set to EARTH. 4. Pull the pendulum up to or below one of the red marks on the protractor (on the left or right side). 5. Write down data here (with units) for a. Starting Angle: b. Mass: c. Length: 6. Describe the potential energy, kinetic energy, and total energy for the pendulum at the top, middle, and bottom of a swing. Sketch the graphs below and describe the data in 1‐2 sentences. 7. Now, repeat, but turn on Friction, up to the middle value or “lots” on the slider, and turn speed to either ¼ or 1/16 to slow down the simulation. 8. Write down your data as above, sketch, and describe the new bar graphs. NAME_____________________________________PERIOD_________DATE Energy of a Pendulum PHET activity Analysis questions – Respond to these questions in a complete, well‐written paragraph. 1. Describe the effect of friction on the potential, kinetic and total energy of the pendulum. In particular, where in the swing is the most thermal energy lost? Where in the swing is the least thermal energy lost? What happens to the total energy over time? What happens to the kinetic and potential energy over time, once friction is introduced?