All you need to do is to time how long it takes the pendulum to do a complete swing. There are no prizes, no score, no nothing. But by doing it you'll be helping to answer questions about one of the most basic science experiments.
You can play around with the controls above to change how the pendulum swings, and to set up markers which might help you make better measurements. You can measure as many or as few swings as you like. Don't be shy - try it out!
Every time you make a measurement, the results get sent to our server. Once we've got enough data we hope to be able to answer some really basic questions about how to time a pendulum swing. With a bit of luck, we should be able to prove or disprove an old bit of physics folklore that no-one has ever checked before.
We plan to publish our analysis on the site, and make the data available for others to analyse - we think there's potential for some great school projects in there. If you want to be kept up to date with what we're doing, then use the button below to follow us on Twitter (@ThePendulumExp).
This web experiment is run by Jony Hudson who works in the Physics department at Imperial College London. He likes making very careful measurements of very simple things, in order to see if there is anything interesting hidden in the details.
Thanks for helping science! Please ask your friends to help too :-)Tweet Follow @ThePendulumExp