4.Two speakers are driven by the same oscillator of frequency 200 Hz. They are located on a vertical pole a distance of 4.00 m from each other. A man walks toward one of the speakers in a direction perpendicular to the pole.

a) How many times will he hear a minimum in sound intensity, and
b) How far is he from the wall at these moments ?

Take the speed of sound to be 330 m/s and ignore any sound reflections coming off the floor.

The approach to this question will be very similar to the other one. The only difference is in the way you compute the distance from the two speakers. In the other problem, the points of interest were in line with the speakers, so it's a simple subtraction. Here, you have to use the Pythagorean theorem to compute the distance to one of the speakers. Otherwise, it's the same thing. Just solve to find all the places where the waves are 180 degrees out of phase with each other.