posted by kimberley .
A soft-drink bottle resonates as air is blown across its top. what happens to the resonant frequency as the level of fluid in the bottle decreases?
Consider the level of fluid in the bottle to be adjusted so that the air column above it
resonates at the first harmonic. This is given by f v 4L . This equation indicates that as the length L
of the column increases (fluid level decreases), the resonant frequency decreases.