The pendulum swings back and forth.
The program recognizes the following commands. The command may be executed by either clicking the button with the mouse (first column below) or by pressing a key (second column below). The mouse buttons may be removed from the screen by pressing the M key. Press M again to restore buttons.
| stop | s | Pauses animation. Press stop again to resume animation. |
| a_normal | n | The normal component of the acceleration is drawn on the screen. Press a normal again to toggle this feature off. |
| a_tangent | t | The tangential component of the acceleration is drawn on the screen. Press a tangent again to toggle this feature off. |
| a_total | a | The total acceleration vector is drawn on the screen. Press a total again to toggle this feature off. |
| top | u | The animation pauses when the pendulum reaches the top of its swing. Press stop to resume animation. |
| bottom | d | The animation pauses when the pendulum reaches the bottom of its swing. Press stop to resume animation. |