An avalanche of sand along some rare desert sand dunes can produce a booming that is loud enough to be heard 10 km away. The booming apparently results from periodic oscillation of the sliding layer of sand – the layer’s thickness expands and contracts. If the emitted frequency is 90 Hz, what is the period of the thickness oscillation?
This problem is too easy but I thought the premise was an interesting bit of trivia. Anyways, period is the reciprocal of frequency
What is the wavelength of the sound?
Wave speed is related to wave length over period. We can solve for wave length and plug in our knowns of speed of sound and period:
Taller than I am, that’s for sure.