Physics
Kunal and Abhimanyu were waiting to go cross a railway crossing. Kunal jumped over the barrier and curiously put his ear on the railway track. Abhimanyu opposed Kunal and pulled him away from the railway track.
(a) Why did Kunal put his ear on the railway track?
(b) Why did Abhimanyu pull Kunal away from the railway track?
(c) Name the waves used for sound ranging. State one reason for their use.
Answer
(a) Kunal put his ear on the railway track to get an idea of the distance of the incoming train as sound travels faster in solid medium.
(b) Abhimanyu pulled Kunal away from the railway track because it is not safe to be on or very near the railway track when the train is coming.
(c) Ultrasonic waves are used for sound ranging. Ultrasonic waves can travel undeviated through a long distance and so they are used for sound ranging.
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