A sound source ( S ) emits frequency of `180 Hz` when moving towards a tigid wall with speed 5 m / s and an observer `(O)` is moving away from wall with speed 5 m / s. Both source and observer move on `(z)` straight line which is perpendicular to the wall as shown in figure. Find the number of beats, per second heard by the observer. (Speed of sound 355 m / s).
'(##CEN_KSR_PHY_JEE_C17_E01_030_Q08##)'

Answer

5