A sound source emits frequency of 180 Hz when moving towards a rigid w – McqOptions

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1.	A sound source emits frequency of 180 Hz when moving towards a rigid wall with speed 5 m/s and an observer is moving away from wall with speed 5 m/s. Both source and observer moves on a straight line which is perpendicular to the wall. The number of beats per second heard by the observer will be [Speed of sound = 355 m/s]
A.	5 beats/s
B.	10 beats/s
C.	6 beats/s
D.	8 beats/s
Answer» B. 10 beats/s

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