Give me a second
This video and student worksheet set a challenge for students to make a pendulum that has a period of one second. The video explains how the frequency of a pendulum will change with its length, and how gravitational potential energy is transferred to kinetic energy (and back again) through each pendulum swing. The experiment can be carried out at home or in school, and links to topics of scientific enquiry, energy transfers, frequency and time.
Students are encouraged to take repeated measurements and to submit their results to the National Physical Laboratory website. The link is in the worksheet.
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