Two loudspeakers are placed on a wall 3.00 m apart. A listener stands 3.00 m from the wall directly in front of one of the speakers. A single oscillator is driving the speakers at a frequency of 600 Hz.
a) What is the phase dissimilarity between the two waves when they reach the observer? (Your answer must be between 0 and 2π.)
b) What is the frequency closest to 600 Hz to which the oscillator might be adjusted such that the observer hears minimal sound?