Question

2 very small, identical speakers, each radiating sound uniformly in all directions, are placed at points S1 and S2 as in Figure 8. The speakers are connected to an audio source in such a way that they radiate in phase, at the common wavelength of 2.00m. Sound propagates in air at 338m/s. Point M, a nodal point, is 7.0 m from S1 and more than 7.0m from S2. Find 3 possible distances M could b from S2