Abstract
Two tuning forks with slightly different frequencies give beats.
Portable
Yes
Principles Illustrated
The addition of a small lump of Blu-Tack to a tuning fork changes its frequency. When struck along with a matching fork that has no Blu-Tack, beats result.
NCEA & Science Curriculum
PHYS 3.3, PHYS 3.4
Instructions
The forks in the photo above nominally produce 256 Hz. The addition of the Blu-Tack results in beats at a few Hz. You can adjust the increase the beat frequency by adding a larger lump of Blu-Tack. The forks have to be held near the head.
Safety
Individual teachers are responsible for safety in their own classes. Even familiar demonstrations should be practised and safety-checked by individual teachers before they are used in a classroom.
Related Resources
Beats from speakers || Combining Sounds
Teaching Resources
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References
Related to PIRA 3B60.10
Credits
This teaching resource was developed with support from
The MacDiarmid Institute
Faculty of Science, Victoria University of Wellington
School of Chemical and Physical Sciences, Victoria University of Wellington