A train moves toward a stationary observer at a speed of 34 m/s. The train sounds a whistle and its frequency registered by the observer is f1. If the train's speed is reduced to 17 m/s, the frequency registered is f2. If the speed of sound is 340 m/s then the ratio f1/f2 is:
Correct answer: D. 19/18
- A. 18/19
- B. 1/2
- C. 2
- D. 19/18
Explanation
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