Problem regarding sounds and waves

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The discussion centers on the propagation of sound through different mediums in a 1200-meter iron pipe filled with water. When a sound is made, two distinct sounds are heard at the other end due to sound traveling through both the iron and the water, with calculated travel times based on their respective speeds. The first question involves determining the time difference between the two sounds, while the second question, now clarified to involve a 400-meter pipe filled with air, asks if two sounds will still be produced. The key difference lies in the mediums: sound travels much faster in solids like iron compared to gases like air. Understanding these principles clarifies the behavior of sound in various environments.
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Homework Statement


An iron pipe is 1200 meters long and is filled with water. If a sound is made at one end of the pipe, two sounds/noises are heard at the other end. If the speed of sound in water is 1450 m/s and the speed of sound in iron is 5220 m/s then
Q(1) : How long is it going to take to hear the second sound at the other end after the first one?
Q(2) : If the pipe is filled with air in which the speed of sound is 340 m/s, will making a sound at one end produce two sounds at the other end?

Homework Equations

The Attempt at a Solution


Well I know that, d=vt and in the case of echo it's 2d=vt but in this case, it's no echo and there are two mediums here which is confusing me and I can't even understand why I'll hear two sounds at other end for the first case.
 
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Nazif Farhan said:
Well I know that, d=vt
That's really all you need.

Nazif Farhan said:
I can't even understand why I'll hear two sounds at other end for the first case
Because sound travels both in the iron of the pipe and in the water filling the pipe.
 
Thanks for the reply Doc Al. Well that solves the first question but you didn't say anything about the second one or maybe you did and I'm not getting it. Please reply, I'm not that bright.
 
What do you think? Compare the second with the first. Any fundamental difference?
 
Oh I'm really really sorry. I left out an important part of the question. In the second question, it should've been 'If the pipe is 400 meters long and if the pipe is filled with air in which the speed of sound is 340 m/s, will making a sound at one end produce two sounds at the other end?'
 
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