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ERIC Number: EJ1174741
Record Type: Journal
Publication Date: 2018-May
Pages: 6
Abstractor: As Provided
ISSN: ISSN-0031-9120
"C" at the Belfry
Semay, Claude; Lo Bue, Francesco; Mélin, Soizic; Michel, Francis
Physics Education, v53 n3 Article 035015 May 2018
In 1849, Hippolyte Fizeau determined the speed of light in a famous experiment. The idea was to measure the time taken for a pulse of light to travel between an intense light source and a mirror about 8 km away. A rotating cogwheel with 720 notches, that could be rotated at a variable speed, was used to chop the light beam and determine the flight time. In 2017, physicists and technicians of the University of Mons in Belgium reproduced the experiment with modern devices to allow members of the public to measure the speed of light themselves. The light source used was a low power laser, and the cogwheel was replaced by an electrically driven chopper, but the general spirit of Fizeau's experiment was preserved. The exhibition was organised in the belfry of Mons, a baroque-style building classified as a UNESCO World Heritage site. The solutions found for the main problems encountered are presented here to help colleagues intending to reproduce the experiment.
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Publication Type: Journal Articles; Reports - Descriptive
Education Level: Secondary Education
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A
Identifiers - Location: Belgium
Grant or Contract Numbers: N/A