8 b from Risskov School presents. M u s i c a n d M a t h e m a t i c s. Tones in Glass. 12 tones in one octave. Spreading of the 12 tones by means of The starting point is the concert pitch a a has a frequency of 440 Hz When you multiply with , you get the tone above
Tones in Glass
We have examined if the following has an impact on tones in glass:
Thesis: When the water gets warmer, the tone becomes deeper.
Conclusion: Temperature has no influence
Thesis: There is a connexion between quantity of water and frequency.
Our researches showed:
Conclusion: We were wrong!
Thesis: It makes a difference to put other materials than water in the glass.
Vi made experiments with:
The speed of one oscillation/wave in pure water
The speed of one oscillation/wave in 10% salt
1/0,001 s = 1000 Hz
10 % salt:
1/0,0012 s = 833,33 Hz
Percentage the ”salt-frequency” is less than the ”water-frequency”:
(1000 Hz – 833,33 Hz)/1000 Hz · 100 = 16,7 %
Method to find the frequency of the tones
This is how we have found all our tones.
Science Workshop-program. By the use of a microphone the program shows a tone’s speed of one oscillation/wave.
The speed of sound in air is 340 m/s
The speed of sound in glass is 5000 m/s
Wavelength = speed/frequency
The tone cis in glass: 5000 m/s / 555 Hz = 9 m
The tone cis in water: 340 m/s / 555 Hz = 0,61 m
Percentage the wavelength in glass is bigger than the wavelength in air (the tone cis):
(9 m – 0,61 m)/0,61 m · 100 = 1375 %