Two loudspeakers in a plane, 5.0m apart, are playing the same frequency. If you stand 14.0m in front of the plane of the speaker
s, centered between them, you hear a sound of maximum intensity. As you walk parallel to the plane of the speakers, staying 14.0m in front of them, you first hear a minimum of sound intensity when you are directly in front of one of the speakers.-What is the frequency of the sound? Assume a sound speed of 340 m/s.
On a topographic map, the closed circles are meant to represent a hill. So if the contour lines are creating a group of concentric closed loops then it must be an indication of a hill.
