JEE Advanced Model Paper 16 with solutions for online practice

A sound source emits frequency of 175 Hz when moving towards a rigid wall withspeed 5 m/s and observer is moving away from wall with same speed 5 m/s. Bothsource and observer moves on a straight line which is perpendicular to the wall. Thenumber of beats per second heard by the observer will be [Speed of sound = 355 m/s]Source is in between observer and wall.