Two passenger trains moving with a speed of 108 km/hour cross each oth – McqOptions

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1.	Two passenger trains moving with a speed of 108 km/hour cross each other. One of them blows a whistle whose frequency is 750 Hz. If sound speed is 330 m/s, then passengers sitting in the other train, after trains cross each other will hear sound whose frequency will be [MP PMT 1991]
A.	900 Hz
B.	625 Hz
C.	750 Hz
D.	800 Hz
Answer» C. 750 Hz

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