Two passenger trains moving with a speed of 108 km/hour cross each other. One of them blows a whistle whose frequency is 1500 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
1250 Hz
625 Hz
1500 Hz
900 Hz
As we learnt in
Frequency of sound when source & observer are moving away from each other -
- wherein
Speed of sound
Speed of observer
speed of source
Original frequency
apparent frequency
Here both are moving away from each other
Option 1)
1250 Hz
This option is correct.
Option 2)
625 Hz
This option is incorrect.
Option 3)
1500 Hz
This option is incorrect.
Option 4)
900 Hz
This option is incorrect.