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Question
Two straight parallel railway tracks are separated by a distance of 20 m. Two trains start simultaneously with speeds 54 km/hr in opposite directions from A and B as shown. They have identical frequencies of their horns which is 660 Hz. Find the frequency of the horn heard by any of the train driver due to the other, 15 min after the start
- 560 Hz
- 460 Hz
- 360 Hz
- 660 Hz
The correct answer is: 660 Hz
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