A source emits a sound and is represented by the red dot in this map. Four people are located around the source, and the circles
represent the sound wave. An illustrations with circles spreading out from a point. On the left the spacing is very close together and on the right the spacing is farther apart. There is an A farthest left and a D farthest right. Just to the right of the dot is C and bove that B. As the source moves west, which person hears the highest pitch? Person A person B person C person D
When a sound is produced by a stationary point source , moving waves are produced around it in circles consisting of compression and rarefaction . These compression and rarefaction are mutually equidistant. But when the source moves in a particular direction , waves get compressed in that direction . If in a distance of V , n number of waves are formed , in case of moving source , same no of waves will lie in V - v distance in the direction of motion. . Here V is velocity of sound , v is velocity of source and n is no of waves being produced per second. So we see that distance between two consecutive waves becomes smaller . Or , waves get compressed . In this region frequency becomes greater.
A is standing left of source and source is moving towards left , hence A. will hear highest pitch or greatest frequency.
