A small sound focus beeps frequency of 1,700 Hz, which is immersed in a lake at a depth of 23 m. A receiver is immersed in the same lake at a depth variable. When the receiver runs on its vertical distance of 800 m from the source of sound, sounds periodically perceived high and low intensity.
a. He explains that the phenomenon is happening. Explain.
b. Calculate the vertical distance between two consecutive receiver positions corresponding to two maxima.