This website is part of, which was developed by LIGO scientists in Birmingham, UK. You will only be able to run this activity using Firefox browser, and you must first ensure that you have the updated Java plugin, See the instructions linked above in Section 2)  for how to update the Java on your local machine (either Windows or Mac).

This applet models a pendulum that is forced to oscillate. Please use the sliders to adjust the length of the pendulum and the frequency and amplitude of the forcing. Try small amplitudes with various frequencies and watch how the pendulum reacts. Is it what you expect? Try using large amplitudes with various frequencies. Are you surprised by the reaction of the pendulum under any of these conditions? Will your students nd any of this surprising? The applet has a radio button that lets you simulate a compound pendulum with two elements. Try exciting that pendulum to see how the motion of the bob changes. Does the compound pendulum provide better isolation from motion than a single pendulum?

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