Speed of Sound

For summer session I opted to use the RipStik for the introduction to waves. I used a modification of the set-up I deployed last spring. The new floor tile, which had an uneven surface, was an unknown factor in the summer run. I used a larger towel. I did use blue food dye, but not enough that it made any difference. The towel was again wet. The results were, if anything, better than those in the spring.
I remembered to time my swizzle. The two sheets were 165 cm in length, which I covered in 1.57 seconds during a second run for a linear speed of 105 cm/s. By good fortune there were four wavelengths on the paper for a wavelength of 41.3 cm. The period was 0.393 seconds, and the frequency of the swizzle was 2.55 Hz. Multiplying the frequency by the wavelength yields a wave speed of 105 cm/s. The amplitude was on the order of 4 cm.
Laboratory nine moved on to measure the speed of a sound wave using echoes. Paulo works on clapping the boards.
Brenna tracks the time while Lilly-Rose looks on.
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