Two trains are moving towards each other with speeds of 20m/s and 15 m – McqOptions

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1.	Two trains are moving towards each other with speeds of 20m/s and 15 m/s relative to the ground. The first train sounds a whistle of frequency 600 Hz. The frequency of the whistle heard by a passenger in the second train before the train meets, is (the speed of sound in air is 340 m/s)
A.	600 Hz
B.	585 Hz
C.	645 Hz
D.	666 Hz
Answer» E.

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