Pendulum Lab analyze pendulum actions. Play with one or two pendulums and discover how the period of a simple pendulum depends on the length of the string, the mass of the pendulum bob, and the amplitude of the swing. It's easy to measure the period using the photogate timer. You can vary friction and the strength of gravity. Use the pendulum to find the value of g on planet X. Notice the anharmonic behavior at large amplitude.

Sample Learning Goals
1. Design experiments to describe how variables affect the motion of a pendulum
2. Use a photogate timer to determine quantitatively how the period of a pendulum depends on the variables you described
3. Determine the gravitational acceleration of Planet X
4. Explain the Conservation of Mechanical Energy concept using kinetic energy and gravitational potential energy
5. Describe Energy Chart from position or selected speeds.

Non-obvious controls:
1. If you want to do an experiment, Pause the sim, set up your experiment, then start it.
2. If you want to compare two variables like length, check Show 2nd Pendulum, Pause the sim, set up your experiment, then start it.
3. The Photogate Timer operates as a triggered mechanism, which starts when the pendulum crosses the vertical dotted line. The period will be displayed after one cycle.
4. Most things are draggable: the timer, stop watch, ruler, tape measure, and energy graph. Also, the entire green control panel is draggable by its border.
5. The initial angle is marked by a tick mark the color of the pendulum mass
6. There is a zoom feature for all Flash simulations. Right click on the sim and select
7. Zoom in. This can be helpful when you are using a projector or writing a lesson where you want a screen shot.

Requirements:
* Java

The license of this software is Freeware, you can free download and free use this calculator software.