As shown in the figure two sources producing sound Sr and Sn (velocity of sound 360 m/sec) each producing sound of frequency 200 Hz. `S_(1)` is rotating anti clock wise where as `S_n` is approaching observer O each with a speed 10 m/sec. (neglect radius of circular path of `S_1`), then calculate

If wind is blowing from right to left with a speed 10 m/sec and observer is at rest find the number of beats received by observer when `S_(1)` is at A. (nearly)

Options

A. 5.5
B. 5
C. 4
D. 11

Answer

A