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Ultrasonic waves

Question: Please explain how to determine the velocity of ultrasonic waves in liquids.


I would suggest that this is best done by an indirect method such as diffraction or interference.
You will presumably know the frequency of your ultrasonic pulses and so if these are transmitted through the liquid and allied to diffract through a slit their wavelength can be found. Hence the velocity of the waves can be determined from:
Velocity = frequency x wavelength

There is a little problem in knowing the size of slit to use but the approximate order of size could be estimated by calculating the wavelength of the waves from their velocity in air or free space (300 000 km/s) and then making some assumptions as to whether you think that they will go faster or slower in the liquid under investigation.

© Keith Gibbs 2010