When the express train approached the nonstop station and sounded a whistle for 5 seconds, I could hear it for 4.8 seconds at the station.
When this train goes away from the station and sound a whistle for 5 seconds, how long do I hear the sound of whistle ?
The speed of the sound assumes 340m per second.
When this train goes away from the station and sound a whistle for 5 seconds, how long do I hear the sound of whistle ?
The speed of the sound assumes 340m per second.
Answer
5.2 seconds
Solution
5 - 4.8= 0.2 second.
This 0.2 second is the time when sound moves forward the distance which this train moves for 5 seconds.
When a train keeps away and sounding it for 5 seconds, time to hear is 5 + 0.2 = 5.2 seconds.
When a train keeps away and sounding it for 5 seconds, time to hear is 5 + 0.2 = 5.2 seconds.
