A train is moving away from an observer at a speed of 50 m/s with its whistle on, the frequency of the whistling sound being 400 Hz. What should be the approximate frequency heard by a stationary observer? Take the speed of sound as 345 m/s when atmospheric temperature is 24°C. 328 Hz O 310 Hz 380 Hz O 349 Hz

A train is moving away from an observer at a speed of 50 m/s with its whistle on, the frequency of the whistling sound being 400 Hz. What should be the approximate frequency heard by a stationary observer? Take the speed of sound as 345 m/s when atmospheric temperature is 24°C. 328 Hz O 310 Hz 380 Hz O 349 Hz