Describe one advantage and one disadvantage of having the water level "sweep" (move) through the resonance position. 5. a tuning fork has a frequency of 384 hz. the speed of sound is 343 m/s. the maximum length of an air column is 80 cm. how many resonances can be observed? lab journal template experiment a: wavelength - determine resonance locations. rvoir ermo- neter a tuning fork is held over the open end of a long tube. the tube is partly filled with water and the tube is connected to a reservoir that is used to change the height of the water in the tube. when the reservoir is high, the water in the reservoir drains into the tube, raising the water level. when the reservoir is low, water drains out of the tube into the reservoir, lowering the water level. the flow of water is not instantaneous, so it is possible to sweep through a range of water levels in a controlled way over the course of a few seconds.