It is well understood in acoustics that a medium is required to conduct sound. Stated in another way, sound is not transmitted through a vacuum. The earliest person to test this experimentally was the Irish physicist Robert Boyle (1627–1691).1 In his experiment, he put a ringing bell under a glass cover called a bell jar. After the air was pumped out, the ringing disappeared. This convinced him that sound cannot be conducted in vacuum. Here we describe an improved version of this demonstration.

Topics
Acoustics, Educational aids, Educational assessment, Physicists
1.
Robert Boyle, New Experiments Physico-Mechanicall, Touching the Spring of the Air and Its Effects (1660).
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© 2003 American Association of Physics Teachers.
2003
American Association of Physics Teachers
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