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A source of frequency 50Hz is moving towards an observer with a deceleration of 2m/s2. If its initial speed is 20m/s, what will be the maximum frequency heard by the observer? Initial distance between source and observer is 100m. Speed of sound = 330m/s.

A source of frequency 50Hz is moving towards an observer with a deceleration of 2m/s2. If its initial speed is 20m/s, what will be the maximum frequency heard by the observer? Initial distance between source and observer is 100m. Speed of sound = 330m/s. Correct Answer 53.22Hz

Apparent frequency only depends on velocity and not the distance between source and observer. So, maximum frequency will be heard when speed is maximum, which is at the start. F = 50(330)/(330-20) = 53.22Hz.

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