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Two trains A and B are approaching a pla...

Two trains A and B are approaching a platform from opposite directions. The siren in the station is making a sound at a frequency 4 kHz. The passengers in trains A and B hear siren at frequencies 4.5 and 5 kHz respectively. Then the velocities of the trains A and B are (velocity of sound in air = `340 m//s)`

A

42.5 m/s ,85m/s

B

75 m/s, 55 m/s

C

85 m/s, 8.5 m/s

D

42.5 m/s ,62.m/s

Text Solution

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The correct Answer is:
B
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